2-step verification (2SV), which is also known as two-factor authentication (2FA) or multi-factor authentication (MFA), helps to keep cyber criminals out of your accounts, even if they know your passwords.
In order to use an Authenticator App you must have logged into AI previously and enabled this feature by following the setup instructions.
If activated, you will be able to use a mobile Authenticator App (of your chosing) to verify/grant login access.