tail light wiring

My tail lights are all messed up. When I cut the lights on and my left turn signal and the brakes all at once. My turn signal flashes so does my right side license plate light and my 3rd row light will flash. My reverse light will also come on with all of that too. Or if the lights are on and I press the brakes my turn signal light lights up too

 

Are you handy? Do you have a multimeter?

If you have a trailer harness start by removing that.

Otherwise, start by inspecting your ground wires. There are a few, and you haven't provided enough info about your truck to do into further detail on that, but in general, there is one next to the battery, one next to the diagnostic port on the intake, and another towards the ECU loom/firewall. On the interior of the cab, there is another ground hiding behind the drivers side kick panel. While you're looking for those, inspect all the wiring you can. It's likely that you have a short somewhere and the contact to ground is turning those various systems on and off. If it's that tied to your headlights, I'd look there... especially if you have non-OEM headlight replacements...