Hal Explains It All

How do you insert a date on each page (word document)?

You have to insert a header and/or footer, and then insert the date into that. To do this:
1) Go to View > Header and Footer
2) Click the cursor in either the header or the footer where you want the date placed
3) Go to Insert > Date and Time
4) Choose what format you want, and whether it should update automatically
5) Format as necessary using the Header and Footer toolbar

Have fun!