Your primary username is the email address you use to sign in to your Google Account.
If you have Gmail on your account, your primary username is your Gmail address. When signing in to Google, you can enter your Gmail address and Google Account password to start using products such as Blogger, Calendar, Drive, etc. If you don't have Gmail on your account, your username is likely an email address that you use, such as a Yahoo or Hotmail address, that you entered when you first created your Google Account. To sign in to Google, enter that email address as your username, along with your password for your Google Account.
If you’ve forgotten your username, we might be able to help you on our account recovery page.