How to divide sections of a book, lock in each chapter

Question

I'd like to divide the chapters of a book into separate sections primarily to lock in each chapter's starting page. This is so alterations of a few lines in preceding chapters don't push the next the next chapter out of place by a few lines.
Thank you.

Answer 1

"When you break the thread (click the outport of the last frame inthe chapter, then click inside the frame)"
Ok, I see that when I click the out port at the end of ch 1, the cursor becomes loaded. Clicking inside the frame, the outport turns to red and ch 2 onwards is no longer visible
"....at the end of the first chapter, the story will go into overset and you will have two sets of threaded frames -- one with the first chapter showing, and the frames beyond that will now be empty, but still threaded to one another."
Yes.
"You cut chapter two along with all the rest of the text to the end of the book from the first thread,"
Ch 2 and the rest of the book onwards are longer visible; how do I cut it?
"....then paste into the empty frames and it will reflow to fill them all again."
I can't try that without following the preceding step correctly.
Thank you.