If you have already enabled two-step authentication via SMS or a mobile app, you have the additional option of adding one or more Touch ID-capable devices, such as a 2017 or newer MacBook Pro and a 2018 or newer MacBook Air. When signing in from these devices, you can use Touch ID instead of SMS or a mobile app to complete two-step authentication.
You will not be able to use Touch ID when signing in from a device that was not added to your account. In these cases, you will need to use SMS or your mobile app to sign in.
If you have not yet done so, first set up two-step authentication by SMS or mobile app.
In macOS settings, go to Touch ID and add a fingerprint if you haven’t done so already. For details, see Apple’s documentation.
In your Profile settings under the Two-step Authentication section, click Add authentication step.
Select Use Touch ID. This option will only appear if your browser supports Touch ID.
When prompted by macOS, touch the fingerprint sensor on the power button.
Next, enter a name for your Touch ID device. This will help you tell them apart if you add multiple Touch ID-capable devices.
The next time you sign in, you will be prompted to use Touch ID for two-step authentication. You can still cancel and opt to use a verification code instead, either through SMS or a mobile app.
Currently, only Google Chrome 70+ supports Touch ID.