If you add Gmail to your Google Account, your account's primary username will permanently change to email@example.com.
After you add Gmail, the original email address associated with your account will become your alternate email address. If you have verified your original email address before adding Gmail, you will be able to sign in using this email address.
Adding Gmail to an existing Google Account
- Go to mail.google.com.
- Fill out the form and click Submit.
- Follow the instructions to verify your account.