The documentation describes using separate fields to create pages for an entry. But how can I create pages arbitrarily? There are multiple reasons I don't want to create a separate field for each page. The Simple Pagination plugin looks like what I want, but it isn't available anymore.
I am not aware of either a built feature or an add-on that will let you break a long entry in to smaller chunks in a way that will let you spread these across several pages, but others might.
There are possibly ways that you could achieve this result within EE without an add-on, but they would be non-trivial solutions to implement.