Question

difference between page margin and page break

Answer 1

page margin is to allin the page and page break is to take new page or to enter on same page.

Answer 2

Page Breaks help to separate content between pages. After a page break, the following text will start at the beginning of the next page.
Section Breaks split your document into sections, enabling you to have different formatting for each section: for example - different page numbering, margins, header/footers, page orientation and borders.