I'm old and stupid so please help: 
I've just been sent an email that is a form to fill in and return ...... but how do I write/type onto the form? I must be missing something here .... I'm sure that there is an easy way to do this but can't see how, any pointers would be most appreciated.
Ta.

I've just been sent an email that is a form to fill in and return ...... but how do I write/type onto the form? I must be missing something here .... I'm sure that there is an easy way to do this but can't see how, any pointers would be most appreciated.
Ta.