Adding two-factor authentication to your online accounts is a great way to stay secure, as it means an attacker will need more than just your password if they want to gain access to your data. Your Google account likely has a treasure trove of data, especially if you use Gmail, so it's probably one of the services you need to protect the most.
If you're not sure how to set up two-factor authentication on your Google account, it only takes about a minute.
Go to your Google account settings
First, go to the two-factor section of your Google account's settings. This link will take you straight there. You can also click on your profile photo on google.com, select 'Manage your google account,' go to the 'Security' section, and finally click the '2-Step Verification' menu.
If you already have some authentication methods enabled, they will be displayed on the page. If not, you should see buttons to enable each method.
Use an authenticator app
If you already have an authenticator app like Authy ready to go, click the Set Up button under 'Authenticator app.' Google will then give you a QR code to scan with your phone. Even though the page says to download Google Authenticator, the code will work with any 2FA app.
After you scan the QR code, Google will ask you to input the login code displayed in the app. That's it!
Other authentication methods
Google also supports several other methods of two-factor authentication. You can set the Google app on your phone to require approval for any attempted logins, similar to how Apple ID logins work on iOS devices. There's also the option to use a physical key like the Yubikey and Google's Titan Keys, if you have one of those.
Google's Titan Security Keys
Finally, Google does allow two-factor codes to be sent over SMS messages, but you really shouldn't use that option. SIM swapping, where someone calls your carrier pretending to be you for access to your number, is becoming more common and could compromise any accounts you have with SMS authentication.