You will see the screen below then click Set it up now
In 'Step 1: How should we contact you' choose a Mobile app from the dropdown
Make sure 'Received notifications for verifications' is selected then click Set up
A 'Configure mobile app' screen should appear. Follow the directions on this screen.
After you install the Microsoft authenticator app, scan the QR code with the app to add account. There is also a 'Code' listed that you can type in manually if you prefer. NOTE: If you are already using the Microsoft authenticator app, open it, click the + sign in the upper right-hand screen, choose 'Work or school account' then scan the QR code.
Click Next on the screen on your computer. NOTE: If you don't do these steps quickly enough it may say that authentication failed. Just do it again but be ready to click the Next button quickly.
On 'Step 2: Let's make sure that we can reach you on your Mobile App device' you will need to approve the notification on the app
In 'Step 3: In case you lose access to the mobile app' screen, add a phone number with country or region code that you will have access to then click Next.
In 'Step 4: Keep using your existing applications' screen click Done.
On the web login page, you will probably need to type in your password again. Click Sign in.
The next screen on your computer will look like the left picture but on your mobile app, you will see a screen like the right picture. Click Approve on the app.
On your computer, you will see this screen. We do not recommend staying signed in but that is up to you.