You just enter your career account password into the screen, which prompts you to open Microsoft Authenticator. You copy over the number on the screen to Authenticator and solve 5 Algebra problems and 3 differential equations. You submit the results but also write down the solutions by hand to mail it over to Microsoft. In around a week when Microsoft gets your responses your solutions are reviewed by a TSA-trained agent for authenticity. Once they confirm it is indeed you trying to access your Purdue email, they send a notification to your phone. You unlock your phone by typing in your password, scanning your fingerprint, face and retina and answer your 3 secret questions. Finally, you enter the number on the screen once again and violla you can now read the spam email in your Purdue mailbox.