tailight bulb???

[MONSTERMATT]

Bottom tailight on the right side is out, it is a brake light the one on the bottom in the bumper of the truck, how do i get in there to replace it, im hoping this is what the problem is, its funny thou cuz when i hit the key fob to lock the truck it flashes but when u hit the brake pedal nothing, WTF?? first of all how do i get in there??