Go to View | Headers and Footers, put your cursor where you want the page
number, and type the text below. The curly brackets have to be entered by
hitting control-F9, you cannot type them. You probably will have to type
from the outside in, adding brackets as necessary to nest the fields within
each other (each pair of brackets { } denotes one field).
Hitting Alt-F9 will toggle the field between showing field codes (with
brackets) and field results (the actual page number). Hitting F9 will
update the field result if the pagination changes.
Note that if you are using Word to generate a table of contents, this is not
the best solution for you, as the TOC will not pick up the field result but
the simple {page} field.
DM