How to display FlowDocument on different pages?

Question

WPF

Faced such problem, in process of creation of the small text editor.
I don't quite understand how the FlowDocument container paginates content. Or rather, at what point, for example, the same Word can understand that it's time to move to a new page?
From which a reasonable question arises: if I want to display a large document on different visual pages on the UI, then how best to implement this? Should there be a RichTextBox for each visual page, or is it better to write your own container for displaying and editing a FlowDocument (which, obviously, will be worse than the richbox itself), splitting the content into different pages?
I have already asked this question on another service .