You can enroll multiple devices using the same TOTP QR code, just scan it more than once. They will generate the same code sequence and the site won’t know the difference.
You can even save the QR code and enroll a new device later if you want.
You can even save the QR code and enroll a new device later if you want.
You could even save it in an application like KeepassXC. Then you turn on the TOTP mode and presto, you have another TOTP device