... in those 3 dots options above

- which means that:

*If you choose 'Visibility Public' - it's 'Standard' 

( I mean you don't even have to 'choose it' - if you want to make it public - because All Chapters are 'Initially Public' = Visible for Everyone :)

*But if you choose 'Private' 

- your chapter won't be visible to all 

( just to a group of users who follow you )