If you have enabled 2FA on your device and are required to switch to a new device, you can refer to the following:
1, Case you change phones
In this case, you can disable 2FA on the old device in the manual here.
Then you can enable 2FA on the new device as in the following instructions here.
2, In case you lose your phone
When you enable authentication via google, at step 3 you will receive a message stating the code. In case you lose your phone or your phone is damaged, you can reinstall google authenticator app by entering the code you saved above. If you still can not restore your google 2FA, please contact support for advice and answers.