MICROSOFT AUTHENTICATION PHASE:
Beginning in this phase, you will no longer see the traditional username/password screen and will see only the Microsoft login screen. On this screen you will enter your full email address for your username and the SAME password you have always used.
If your account is currently required to use multi-factor authentication, you will proceed to confirm your account with the security methods that you previously configured in Microsoft (push notification via Microsoft Authenticator app, security questions, text, etc.)