A family of Microsoft word processing software products for creating web, email, and print documents.
You have to insert a section break and then you can restart the page numbering for the new section by going to the Page Number Format dialog box (Insert | Page Number | Format Page Number). See also http://wordfaqs.ssbarnhill.com/FrontMatterRibbon.htm.
You can easily keep track of the total number of pages by inserting a NUMPAGES field. However, if you mean that you want to maintain multiple sets of page numbers (one for each section and one for the whole document), note that it would require performing some calculations with formula fields.
In addition, whenever you instruct Word insert a cross-reference to a page number or when you create a table of contents, Word will insert the page numbers as defined by the Page Number Format dialog box.