License plate light burned out

Typically the bulb is accessed right next to the plate behind a lens/dome, either pry out the dome-will have little spring loaded grippers holding it and can be pried out with a thin blade flat tip screwdriver, or remove attaching screws and pull the housing out and then can remove bulb connector typically twisting it 1/4 turn and pull out the bulb, will likely be a 194 "peanut bulb", replace and reverse for reassembly. These bulbs are very inexpensive.