Static + custom database & list content by account or project

Hello - I may just be searching by the wrong terms because this feels like it should be very basic.

If I am selling a saas journaling app with a preset of say 10 static chapters for every new account, how do I set up my database to give those specific 10 chapters every time, but also allow customers to contribute their own chapters for their own personal use?

A step further an account could have several projects with the same 10 preset and unique user-defined chapters for each project.

Thanks!