It is possible but take a look at AutoCorrect and AutoText. They may give you what you want without keyboard remapping. Either or both of these in combination would give you access to far more shortcuts than remapping the function keys.

Automated Boilerplate Using Microsoft Word

I don't think the F1 key can be reassigned because it is already assigned to the Word Help function. That function is active in the keyboard reassignment process. If you check, you will find that all of the function keys already have purposes assigned in Word and some of them are quite useful.

If, after you read the article I linked, you still want to reassign your keyboard, write back and i'll give you some help with it.