It’s not really hard, just time consuming and kinda PITA. Wired cameras are more dependable than wireless but are more work to hookup. Typically, you hook the camera (power to the reverse lights. When you put the vehicle in reverse power supply to the reverse tail lights, and the camera comes on. Typically,You will also have to find a power supply for the monitor. Another option, is to not use the reverse lights but add a switch in the cab that allows you to turn the camera on whenever you want. You have two options for this, switch is always hot meaning even when the vehicle is off you can turn the camera on or you find an ignition hot wire and when the key is in the run position powers provided to the switch, which in turn allows you to turn the camera on. Use quality connections, switches most camera kit come with everything you need except the switch.
The sheep always complain about the Sheepdogs UNTIL the Wolves show up then they beg for help!