Android
Open "Play" store on your phone and look for "Microsoft Authenticator" app, or use the link below:
iOS
Open "App store" on your phone and look for "Microsoft Authenticator" app, or use the link below:
2. Login to your Microsoft account
On "Security info" field, press UPDATE INFO
Choose Add sign-in method
From drop down list, select Authenticator app
Click Add
Click Next
Click Next
Now open "Microsoft Authenticator" app on your phone and choose to add Work or school account
Instead of signing in, choose Scan a QR code
Scan a QR code visible on your PC screen
Wait a few seconds and your account will be added. Click Next
Type the same number you'll see on your pc screen to the Microsoft Authenticator app and select YES
Click Next and you're done.
The next time you will try to login to any service which requires 2FA, you will be asked to enter two numbers on your phone app, instead of typing code from SMS or calls from Microsoft.