On the registration page, you would need to add your new form fields inside the existing registration form.
You will also need to modify t he users table of the database by adding new columns to hold the information from the new form fields.
After you have added the form fields to the registration form and the new columns to your database, you would have to use Digital File Pro to add the image / resume upload functionality.
the final step is to double click the insert record server behavior on the registration page to bind the new form elements to the respective database columns. For the image upload fields, see the "How to apply Digital File Pro to DataAssist Insert and Update pages" tutorial in the How To section of the DFP Support page:
this will walk through getting the file names into the database.