Create a method of saving data

[tomneedshelp]

I have created a form on access which develops a unique username and calculates age automatically,
I need to be able to use a button which adds in that data to the relevant table, but I do not know what coding is required.
Help would be much appreciated
Thanks

[June7]

Should not save calculated age. Calculate it when needed.

If username field is included in the form's recordsource, simply: Me!username = some value here

If username field is not in the form's recordsource, use an SQL UPDATE action.