You can sideload apps onto Android Auto, which will allow you to watch YouTube, among other things, on your car's display.
It'll soon be possible to watch YouTube on your infotainment display while your car is parked.
Android Auto YouTube Limitations: Is It Worth Using In The Car?
The latest NewPipe version includes one of the most anticipated features in the Android community: support for Android Auto and the ability to choose content to listen to on the infotainment screen ...
YouTube on Android Auto is still a forbidden fruit, albeit users have found ways to enable the app in the car and watch videos on the infotainment screen. However ...