How to store user changes?

Question

Database design

I am developing an application in which it will be possible to download various books + search for translations of books. For example, there is a book "Perfect Code", the application will allow you to find a link to the desired implementation of this book (eg in English from a certain publisher). All information will be added by users. Users should be able to add book, genre, book author, source (download link), etc. The user should also be able to change this information. Once information is added or changed, it is only available to the user until the moderator checks that the information is correct.
What is the best way to implement this in a database?
We currently have the following structure:

Answer 1

It is possible, for example, for entities that are added by users, to keep the user id field, and resetting it to zero = "available to everyone"