If you have
enabled two-factor authentication, you may use the same control panel to perform changes.
You may:
Switch between TOTP and SMS
Disable two-factor
View QR code/master key
If you wish to invalidate the current master key, you must first disable the two-factor, and then enable two-factor again.
Keep in mind that you need to add the new master key to Authenticator or any other app you use, just like during initial setup.