Why does the camera on the navigator not work?

Question

satellite navigation

Hello! I bought a navigator ( tinyurl.com/o44kxbj ) and I want to connect an R-camera to it.
AV-in is connected via a mini-jack (the wire was not included), the camera itself turns on when the reverse gear is turned on, a positive wire is additionally extended from the reverse lamp, but there is no input for it on the navigator. It does not respond to the camera connection, I can’t understand how it should work, automatically switch to video when a signal is given or install the camera program?

Answer 1

And why did you decide that this model supports cameras?