You can add page numbers in Word to the header or footer sections of a document using the page numbers option in the Insert menu.

If you run into a conditional header or footer request that you can't handle, take a look at Word fields. They're not magic, but it kind of feels like magic when they do what you want.

Whether you want to use page numbers to distinguish between a novel's preface and main body, a dissertation's introduction and chapters, or a textbook's content and index, using Microsoft Word's ...

Headers/footers are set per-section in Word. There are a variety of types of Section Breaks that you can insert -- some include a page break; others do not.