Car headlights have two beams - low beam and high beam. The best way to check that your car lights are aimed correctly is to face the car toward a wall/garage preferably at night, with your lights on and to slowly reverse away from the wall. Switch the lights between high beam and low beam – the low beam lights should dip to the left.
To check the rear lights slowly reverse back toward the wall. You should also be able to see the stop lights reflected against the wall/garage when you brake. Better still, get a friend to help out and let you know if they are working and aimed correctly.