If you want to show current page and total page of the book/document, then you can use this Page x of y feature. A user can insert it by two ways; from gallery and by inserting code from code field.
Inserting X of Y page number will replace the existing page number that if you already have inserted. the quick and fast way to insert page number X of Y is from page number gallery

Insert X of Y Document from Page Number Gallery
Page Number gallery provide a user ready made page items ready to insert. Just follow these steps to insert X of Y page number.
- Go to INSERT tab
- Go to HEADER and FOOTER group
- Click on Page Number
- Select the location where you want to insert Page number; top, bottom, etc (Remember that page margin location does not provide this X of Y page number feature)

- Scroll Down the gallery page until you find Page X of Y
- You Will find three page number option (Left, Centre and right) in X of Y section. select according to you need and click on it.
- Page X of Y will be inserted successfully.
- Click Close Header and Footer Button or simply double click and where outside the header and footer area .
