I already answered that before. So here it goes:
I wouldn't recommend you to use Google Authenticator since you can't easily backup your accounts with it and it's not tied to your gmail account. This means that if you lose your phone and you haven't saved the 2FA secret code, your 2FA accounts are gone. I suggest you to use a open source app like andOTP (the one I'm using) that allows you to backup your 2FA accounts.
This means that you have 2 options:
a. Save every QR code image or secret code before enabling 2FA.
b. Use a 2FA app that allows you to backup your 2FA accounts (Authenticator Plus, andOTP, etc...).