Sign Up Nickname

When a user signs up is there anyway they can add a nickname? In the supreme theme it shows above the edit button on a listing the First Name, which is bit rubbish as I don’t really want to plaster users personal names all over the website unless they were able tochoose this as a nickname. It automatically adds the email address to nickname and I guess I could replace first name for nickname ion the code but I don’t really wan to show their email address either. Any suggestions? At he moment I’ve set it to display none but I guess I may need to leave it as is or just manually add their business name to their nickname on the back end.

Also, once they have signed up there is no way they can make any changes to their profile (i.e. email address)

Thanks