That’s it! Your dad’s phone should no longer be paired with your car. We should mention though that device names are usually pretty vague, and it can lead to some confusion when you’re removing a paired Bluetooth device.
If you and your dad both had Google Pixel 7 Pro phones, you’ll likely just see “Google Pixel 7 Pro” (or some variation on that) twice, leaving you needing to guess which one is yours. In this case, you’re in for trial and error, or simply removing both devices and pairing your phone again. It’s a rare issue, but one worth mentioning just in case.
We hope this helps, and you can get back to listening to your tunes when you’re driving regardless of who is in the passenger seat!