1) wot is function of tv installed in passo?is it work in Pakistan?
that TV is DVB-T "Digital Video Broadcasting — Terrestrial", it is same like we have PTV, ATV broadcasted through air, but we only have Analog broadcasting in Pakistan, but not any digital broadcast, so right now these TVs dont work here.
2) Does it contain usb port /AUX...?
some models contain a 4-pin port at their back which is the usb port, you need a proper cable otr you can make your own (USB connector at one side, and 4 wires soldered to player's 4 pins at back)
to my knowledge, some models after 2010 have these usb ports, 2010 = W60, 2011 = W61
3) can we install backview camera in it?
yes, you can install a Rear view camera with all of these players, for this they also have a 4-pin connector at their back, and we have to solder the normal Yellow color RCA video cable to these pins.