A family of Microsoft word processing software products for creating web, email, and print documents.
The quickest way to insert page numbers in a Word document is to double-click the header to activate the header/footer view. Then click in the header or footer and insert the page number with Alt+Shift+P.
To restore the missing page number galleries, exit Word and delete the Built-in Building Blocks template. These are stored separately for each installed language.
For example, if you are using US English, you will find the template in the folder at %Appdata%\Microsoft\Document Building Blocks\1033\16.
To open the folder, use the Run dialog box (Windows logo key + R); type or paste %Appdata%\Microsoft\Document Building Blocks\1033\16 and press Enter.