I have three lights on my garage and one at the front door, all lights work on a switch at the front door. How do I wire a photocell at the front of garage to work all the lights.

What kind of photocell?

Many have a white that goes to the neutral, a Black to the line(power), and a red that goes to the lights(load).
You can wire so the switch can be a On override, so you can turn lights on if not dark enough, or wire as an an Off Override, so you can turn lights off, even when dark.