'Joseph thinking'
System window

???: GUHHH!

A man suddenly shot from his bed in a cold sweat, touching his chest and stomach in fright.

???: 'Wait but....but I remember dying....the truck..."

??? 2: Hey Joseph, you alright, buddy?

The now-named Joseph looked at the concerned male. Joseph got a sudden headache, giving a pained hiss as he attempted to soothe it.

Joseph: Yeah....I'm fine, William.

William pats Joseph on the back, giving his friend a kind smile.

William: Well try not to stress too much, man. We're almost fully fledged Imperial Mages, you got this. It's the Final Examination, so....you kind of have to.

William gave Joseph one more pat on the back before leaving. Joseph sat on the edge of his bed, his hands shaking a little.

Joseph: But......but how.....? I.....

Suddenly, a blue screen appeared from thin air in front of him, making him fall back in fright. His eyes widened in recognition, having an idea of what this thing was.

Welcome to the Battlemage system!
Name: Joseph
Title: None
Occupation: Imperial Mage Corps Cadet
Unit: Alpha Company 1-12 - Imperial Mage Training Academy

Joseph: I.....really did die, this isn't a dream. I really got isekaied?

Correct, Joseph.

Would you like to begin the Tutorial?

Joseph: Can you explain this world? I don't know the rules, but I can tell it has magic.

You are on an alternate planet Earth where magic was made widespread in the 1600s with European expansion, but existed for thousands of years. Humans share the planet with Elves, Dwarves, and Beastkin.

Joseph: Wow that's....kind of a lot. What year is it? This place looks like a boarding school from an old British show?

It is the year 1938, and the history is not completely parallel to Earth. You are currently in the country of Avalonia as an Imperial Mage, the elite amongst the Royal Mages.

Joseph nodded as he thought to himself. This world would be incredibly confusing for him, being almost 100 years before his time, but with risk comes opportunity. If magic was really real, even as a soldier, who knows what he'll get into?

Joseph: 'So another world, huh? Maybe a little old for my tastes, but this may be fun.' You said Avalonia? Is that some kind of alternate United Kingdom or America?

Partially correct. Avalonia was a colony created by the Britannian Crown, this world's Great Britain, in the 1700s and was abandoned after 50 years due to the Avalonian Revolution. It is currently run by the Avalonian Royal Family and advised by the parliament.

Joseph: Huh that's.....cool I guess? I mean, it's another British fuck up.

Joseph shook his head, clearing himself of distracting thoughts.

Joseph: Hey system, I'd like to do the tutorial now.

Great! Beginning tutorial now.

Suddenly, everything went black for Joseph. It only lasted a second, maybe even 2, before he was transported to a completely different scene. He was standing in a formation with dozens of other students while an instructor was speaking. They all wore black pants with white shirts and boots, perfect training attire. Instructor Vance, a towering man with a stern visage and the bearing of a seasoned veteran, paced slowly before the line of cadets.

Instructor Vance: Today is the final selection course for you all as Imperial Mage Cadets. Do not mistake the Imperial Mage Corps for the common infantry divisions. While standard conscripts rely on iron and powder, you are the scalpel of the Avalonian military. You have been drilled in five fundamental arts, and you are expected to show proficiency in each and every one of them.

Joseph's breath hitched as the instructor paced back and forth. In his past life, he wasn't a soldier, just an average guy living day by day. All of this is completely new to him, but he'd adapt. It's not like he has any other choice.

Welcome to the Tutorial! 
As you perform the Final Examination, you will be explained each of your stats.

Instructor Vance: Cadets Smith, Obren, Jones, Isaac, Hills, Thatcher, McClenathen, proceed.

Cadets: Yes, sir.

Joseph and the other named Cadets walked through the hallway and into the first testing chamber. In it was a set of target dummies and several instructors, all of whom took one Cadet and brought them to a range. Joseph gave his instructor his examination sheet.

Instructor: This is the magical portion of the Final Examination. It's simple, shoot each target with a different magical attack. What's your name?

Joseph: Cadet Joseph McClenathen, sir.

He nodded and wrote something on a clipboard.

Instructor: You may proceed when ready.

Time came to a standstill as everything went gray. The system window then popped up, signalling this was the tutorial.

Magic is the integral part of being a mage, and the Imperial Mage Corps are one of the mages who have it down to a science.
Magic is measured in individual Mastery. Mastery determines how strong an individual ability is.
Magic damage is calculated based on Intelligence. The Intelligence stat does not measure the host's actual intelligence, but a higher stat makes it easier to learn new material.

Joseph nodded, looking at his hand.

Joseph: So what magic do I have?

Host has 6 particular brands of magic. The first is Flamecharm, the Imperial Mage discipline of Fire Magic.
Note Flamecharm is the simplest of the disciplines and the most balanced.
Host has the advantage of the system.
Merely think of the magic you would like to use and imagine it being done.
Be warned that the host is responsible for aiming and attacking. The system simply removes the need for complex focusing.

Joseph nodded and held his hand out. Just like the system said, he only needed to think, and a fireball suddenly ignited in front of him.

Joseph: 'Woah.....'

Grinning, Joseph hurled the ball of fire at a target dummy, watching it get engulfed in a small, fiery explosion upon impact. Joseph looked at his hand with a smile, feeling the heat of the magic within him.

Joseph: 'So this is what magic feels like?'

Well done.
Your next magic is Frostdraw, the Imperial Mage discipline of Ice Magic.
Note Frastdraw is the slowest of the disciplines, but is ideal for a defensive approach

He looked at the next target and focused, pulling a massive spear of ice from thin air. With a snap of his fingers, he sent the spear flying, piercing the dummy's chest.

Joseph: 'So cool.....hehe.'

Well done.
Your next magic is Galebreath, the Imperial Mage discipline of Wind Magic.
Note Galebreath is the fastest amongst the disciplines.

Joseph straightened his hand into that of a knife before cutting through the air, making a blade of condensed wind and bisecting the training dummy. Joseph was surprised at how clean the cut was from his perspective.

Well done.
Your next magic is Shadowcast, the Imperial Mage discipline of Shadow Magic.
Note Shadowcast has the lowest combat power, but the highest sabotage potential.

Joseph: 'Well, that figures. What am I gonna do?'

Joseph thought for a moment, unsure of what to use shadow magic for hearing that. He held out his hand, focusing so that dark particles danced off of it. The same particles appeared on the target dummy before ripping it from its stake. 

Well done.
Your next magic is Thundercall, the Imperial Mage discipline of Lightning Magic.
Thundercall is widely regarded as the most unpredictable magic in an Imperial Mage's arsenal.

Confident, Joseph raised his hand, feeling the static electricity build up. He snapped his fingers, and a bolt of lightning flew from his hand to the dummy, obliterating the target and charring the ground.

Instructor: I see here you're part of the Hexad Generation. Demonstrate your Ironsing magic.

Ironsing is a very rare magic for humans to possess.
Amongst the mages of Avalonia, the majority of Ironsing holders act as Ordnance and metalworkers.
Ironsing is the most versatile of the Imperial Mage disciplines

Joseph grinned, a bit more than he intented do. He conjured an iron chain and threw it at the training dummy, spearing its head before violently yanking it off. The Instructor was admittedly disturbed, but he noted the results down on the grading sheet. After a bit, he gave Joseph the paper.

Instructor: Go to the physical portion of the exam. Just follow the arrows painted on the walls.

Joseph: Yes, sir.

Joseph walked through the halls as the system window fed him information.

Magic damage is calculated from both individual Mastery and the Intelligence stat.The current levels measure as follows:
Flamecharm - Mastery 10Frostdraw - Mastery 10
Galebreath - Mastery 10
Shadowcast - Mastery 10
Thundercall - Mastery 11
Ironsing - Mastery 11
Intelligence (INT) - 15
Magic damage is a Magic's Mastery plus ½ of Intelligence. In the case of odd numbers, the Intelligence factor is rounded up by 1

Joseph: Why are Thundercall and Ironsing so high? And what's with that Intelligence stat?

Host's body previously excelled in using Thundercall and Ironsing together, hence the bump in Mastery.
Intelligence was determined by the host's actual intelligence and the body's chosen job as an Imperial Mage. 

Before Joseph could ask any more questions, he arrived at the physical testing area. The training hall was massive, with padded floors and walls, and wooden racks of blunt training weapons lining the sides. He gave the instructor his grading sheet.

Instructor: The physical portion of the exam tests your ability to fight without magic, or when your magic is suppressed. For swordsmanship, you will face an automated puppet.

A mechanical wooden dummy dropped down from the ceiling. The Instructor pressed a button on a remote, and the dummy lunged forward, its wooden sword raised high. Joseph's body moved on its own. It was like muscle memory took over, sliding him past the dummy's strike. With a fluid motion, he grabbed a wooden training sword from a nearby rack and brought it down in a sharp arc against the dummy's shoulder. A loud crack echoed through the hall as the wooden sword connected, and the dummy's arm hung limp.

Swordsmanship falls under the physical category and scales with your Strength (STR) stat.
All physical damage scales from Mastert + ½ of Strength.
Your current Strength stat is 11.

The dummy tried to use its free arm to swing at Joseph, who used his sword to block and kicked the dummy square in the chest, sending it sprawling.

Congratulations, Host has unlocked the skill: Hand to Hand Combat
Current Mastery: 5

Joseph: 'That.....holy shit that sucks!'

The dummy got back up, surprisingly durable, but Joseph was faster. He stepped in, feinting high before going low, sweeping the dummy's legs out from under it. As it fell, Joseph drove the pommel of his sword into the dummy's chest. The machine slumped motionless.

Instructor: Good work. Next is the marksmanship range.

Joseph took his paper and went to the range, which was pretty much what you'd expect from a range. It had a high-tech-for-the-1930s look, with the smell of gun oil and powder hanging heavy in the air. He gave his paper to the instructor there, who handed him a bolt-action rifle after a quick read.

Instructor: You'll shoot 4 iterations, 1 for each target.

Loading the rifle, Joseph racked the bolt and took aim down the iron sights at a distant target. His breathing slowed, his heart rate dropped, and the world narrowed down to the front sight post. 

Joseph: 'Wow, I really know how to use this thing. I never touched a gun in my past life.'

Unlike magic damage and physical damage, damage with ranged weapons is dependent on Marksmanship Mastery
Current Mastery: 10

Instructor: Weapons free.

Timeskip
It took a while, but Joseph finally finished the system's tutorial and got to look at his full status list.

STR (Strength): 11
CON (Constitution): 12
AGI (Agility): 11
WIL (Willpower): 10
INT (Intelligence): 15

Skills
Flamecharm
Mastery - 10

Ironsing
Mastery - 10

Frostdraw
Mastery - 10

Thundercall
Mastery - 10

Galebreath
Mastery - 10

Shadowcast
Mastery - 10

Swordsmanship
Mastery - 10

Marksmanship
Mastery - 10

Hand-to-Hand Combat
Mastery - 3

The instructor handed him his folder.

Instructor: Give this to your Head Instructor.

Joseph: Yes, sir.

Joseph left, sighing a bit. While it was still a test, he'd be lying if he said he didn't think it was fun. Tutorial or not, he'd be in hot water right after, since he had just done the combat stuff and not the real stuff that being a soldier entailed, but he knew a bit about commands and customs, thanks to the system. After a few minutes of walking, he made it to the Head Instructor's desk with the file in hand.

Joseph: Sir, this Cadet has finished his Final Examination.

The Head Instructor took the folder and opened it, giving an impressed whistle.

Head Instructor: High marks across the board, although you're a little violent with your Ironsing magic. You're free to retire for the day, Cadet McClenathen.

Joseph: Thank you, sir.

Joseph turned heel and walked away, taking the long route to his dorm room.

Joseph: Fuck, my body's a little sore. Hey system, is there a way I can improve my stats? That Hand to Hand Mastery is abysmal.

Yes. Stats and Mastery both grow from training.
As you gain levels, both become harder to level up through conventional training means.

Joseph: Conventional means?

Conventional means are traditional training methods.
Stats like STR or AGI can be done through physical training, but some unconventional methods work.
Example: Wearing ankle weights throughout the day will improve the AGI stat.
Mastery is improved through constant activity, meaning the more you use a skill, the more it improves.

Joseph: So it's like real-world skills, huh? At least numbers go up, brain go happy.

Joseph made it to his room and flopped onto his bed, seeing that he was by himself.

Joseph: Hey system, what exactly is my Imperial Mage job?

Your job is a Bureaucratic Affairs Specialist.
Anything about paperwork, be it supply invoices, investigation reports, or disciplinary forms, you fill, review, sign, and file them.
It's considered a high-profile job in the Imperial Mage Corps, as it deals with every aspect of a unit's everyday operations.

Joseph: So.....I'm a glorified paper pusher? Lovely.

Joseph conjured his status window, looking at his skills and stats.

Joseph: Job aside....I've got some work to do.

A week goes by, and the Cadets spend time cleaning up and preparing to be shipped off to their respective units. The Imperial Mage Corps has 3 distinct units: The 1st Regiment, the 2nd Regiment, and the 3rd Regiment. The 1st Regiment is known for being the best and elites, full of Royal Mages and combat units led by Imperial Mages that go out first when a conflict happens. The 2nd Regiment is full of the reserve component, Imperial Mages, who are no less skilled but do more logistical duties, get stationed here, and are sent after the 1st Regiment during wartime. The 3rd Regiment is the secondary reserve component and National Guard that stays within Avalonia to protect the country itself. Joseph finally received his full uniform, complete with his shoulder insignia. 

It was a black double-breasted coat with black uniform pants. Under the coat was a white uniform shirt and a black tie, and on the right pocket was a nameplate with 'McClenathen' engraved into it. For footwear, he had a pair of cavalry boots that went halfway up his calves. His unit patch was on the right sleeve of his uniform. On his lapels were a pair of crossed feather-like rhombus pins, his rank insignia to show he's a Mage, the second rank in the Imperial Mage Corps. Most were Apprentices, so he was a little confused as to the sudden bump in rank. He was assigned to the 1st Regiment, or the King's White Dragons.

As he adjusted his tie to look proper, William wrapped an arm around his shoulder with a grin. His uniform was the same, only he had a different insignia, and his rank was Apprentice.

William: Dude, I can't believe we're graduating today! And you're a Mage in the 1st Regiment!

William sheepishly showed his own insignia. It belonged to the 2nd Regiment, also known as the King's Royal Griffons. 

William: I was assigned to the 2nd Regiment, but that's what I get for picking a non-combat role. It's hard to find jobs like that as an Imperial Mage.

Joseph: Don't feel bad, I'm a Bureaucratic Affairs Specialist, basically a pencil pusher.

William: At least you'll see action if something happens. The 2nd is basically logistics; they see less combat than the 1st. Plus, doesn't the 1st have lots of Royal Mages and Infantry?

Joseph: Yeah, and some Field Artillery battalions.

The two walked down the hall with their hats under their arms. Just then, Joseph bumped into someone. She was a tall girl with a head of long auburn hair that reached past her chest. Her skin was fair, with a bit of tan, and her eyes were a striking blue. She wore an identical uniform to Joseph and William, but she wore a pencil skirt and heels in place of pants and boots. Like Joseph, she was a Mage rank assigned to the 1st Regiment. Her nameplate read 'Ashmore'. She narrowed her eyes at Joseph.

Ashmore: Watch where you're going.....McClenathen.

Joseph: Sorry, Mage Ashmore.

She lightly scoffed before walking past him. William looked at Joseph with a goofy grin.

William: I didn't take you for a guy like that.

Joseph: William, what the fuck are you talking about? I don't even know her.

William: What? Have you been living under a rock? That's Amber Ashmore. You know, daughter of the Conqueror of Flames? The Imperial Mage Wizard who turned the tide of the Great War with his fire magic?

Joseph: I get it, William. I'm saying I don't know her enough to say I like her.

William: Well, my friend, that's why we talk to people. Let your good pal William give you the rundown on how to woo the ladies.

Joseph rolled his eyes but chuckled as William gave admittedly horrible dating advice. He's gonna miss him when he goes off on his own, but he'll talk with him as much as he can before they both go their separate ways. Who knows what'll happen?

So I know this seems rushed. I've been planning and worldbuilding for about 2 months now, but I never thought about how to start it all. So as you can see, this world will be a bit more advanced than ours was in the 30s, and there's gonna be fantasy tropes because of the fantasy elements in it.

The Royal Mages are regular mages with 1 magical affinity and are always assigned to the Army or Navy. And just like any military, not all Imperial Mages are built for combat. Some still have a basic or intermediate level of spells because they do support roles like medics, logistics, or maintenance. 

Also the stats are straightforward, I just couldn't make a tutorial for everything because of some stuff that was happening to me, nothing bad but enough to mess with my writing:
Strength (STR) is how strong he is and how hard he hits

Constitution (CON) is how durable he is and how resistant he is to certain ailments

Agility (AGI) is how fast he is and how well he can move

Willpower (WIL) is how resistant he is to certain magical attacks

Intelligence (INT) is how smart he is and how strong his magic is

And also, I know I did a bad job describing the rank insignia. Here's what they look like. The ranks are Acolyte, Mage, Battlemage, Wizard, High Mage, Archmage (Brigadier, Major, Lieutenant, and Commander)