Backup camera help

Hi everyone. I'm new here. I've read many different threads here but none seemed to be exactly what I was looking for. I have a 2008 Prius with no JBL, no navigation, no AUX, and no backup camera. I have a factory screen and factory radio and I was wondering how to add a backup camera to it. I remember in another thread that somehow the wire harness might already be present inside the vehicle, just hidden somewhere.

I'm not gonna try and install it myself. Definitely leaving it to a professional. Can I just buy a camera and have someone like Best Buy or local car audio store do it or do I need to buy a specific wire harness/adapter with it or will I need an entirely new screen? I want to keep the original screen but if I have to replace it, I will. If I could get to control Spotify through the factory screen via bluetooth, that would be super awesome but I know that's just wishful thinking lol. Thank y'all for all the help