User Function () Pulling data and writing back to Admin Console

I have created and Interface  where I have displayed the Following Fields:

FirstName, Last Name Phone And Email.

When the User initially logs into the application he will be directed to this form, I want to be able to pull the First Name, Last Name Email and Phone from the users table so that the  form shows this information. 

The user will then add there address and submit, I would like the address information that the user added to update the Users table (admin Console). I looked at using User Function however I am getting errors,The though process was to create a rule and assign it to the Interface. 

Any thoughts