Add your other email accounts to Outlook.com - Microsoft Support
Notes: This feature is not supported if you sign in with a work/school account. If you use an authenticator app or other multifactor sign in, you will need an app password to sign in.. If you want to create another email address that uses the same inbox, sent, items, and contact list as your existing Outlook.com account, read how to create an email alias.
Applies To:
Outlook.com