Why tail lights not working

I need help please

Oh, tail lights not working. First check the bulbs, may be burnt, then there is a relay for the tail lights, and a fuse, none of that works then have to determine if there is power going to the plugin under neath the vehicle, and look at what condition the bulb sockets are in. A test light is nice for checking for power if you get to this point.

Where is the relay for the tail lights mine doesn't work nor my back up.lights have running lights front and turn signals all way around and brake lights