Associate username and email

Hi everyone,

How do I associate username and email?
Currently the user accesses the app via email, this is retrieved in the users table, then to upload a photograph I use a Google Sheet where I request a Username via form, I would like the user to write the Username only once by associating it with his email. So that if you publish other photos with the same email, the Username will be automatically recovered without showing it again in the form.
I thank

You can add special components to a form that will retrieve values from the user profile. If you have a username in the user profile table, you can add the component for the username and it will automatically populate every time a form is submitted without the user needing to specify a username.