Hi,
Thank you for writing to Microsoft Community Forums.
The Microsoft Authenticator app helps you sign in to your accounts if you use two-factor verification. Two-factor verification helps you to use your accounts more securely because passwords can be forgotten, stolen, or compromised. Two-factor verification uses a second factor like your phone to make it harder for other people to break in to your account. The Microsoft Authenticator app is available for Android and iOS.
You may also refer these articles for more information:
Download and install the Microsoft Authenticator app
How to use the Microsoft Authenticator app
However, for queries related to Microsoft Authenticator app, let me help to point you in the right direction. I would suggest you to post your query in Microsoft Q&A **** Forum where you will find professionals with expertise on Microsoft Authenticator app and that would be the appropriate forum.
Regards,
Aditya Roy
Microsoft Community – Moderator