A family of Microsoft word processing software products for creating web, email, and print documents.
You can insert the field easily using References | Captions | Cross-reference: Reference type: Bookmark; Insert reference to: Page Number.
Insert the bookmark using Insert | Links | Bookmark. The bookmark must be a single word; it can contain numbers but can't start with one. So you can use LastPage but not Last Page, Page2 but not 2ndPage, etc.