How do I install a parking camera to the screen and also ...

Hello and thank you for using JustAnswer. You would have to buy an aftermarket radio that has a video feed to install a reverse camera. The aftermarket cameras have a different video feed compared to the factory radio setup. If you get the radio with video screen and an aftermarket camera, you can then install it to your reverse circuit and it will come on when you put it in reverse. To fit the lights you can use wire loom to cover the wires.