Hi!
So today i will be listing the colors in Japanese! a picture will also be provided in the end of the chapter!

grey-scale :

shiro 白 / shiroi 白い
White.
kuro 黒 / kuroi 黒い
Black.
haiiro 灰色
Grey. Ash-color.

primary:
aka 赤 / akai 赤い
Red.
ao 青 / aoi 青い
Blue
kiiro 黄色 / kiioroi 黄色い
Yellow.

secondary:

midori 緑
Green.
murasaki 紫
Purple
daidaiiro 橙色
Orange.
( orenji/ オレンジ is another way to say Orange)