You need a very CLEAN garage, an air compressor, and a paint gun.
Then you need a WHOLE lot if time, becasue stripping off the old paint, fixing dents/doing body work, and priming the car takes forever.
Painting a car requires a lot of manual labor. You have to disassemble a lot of the car (remove headlights, trim, engine if you want to paint the engine bay, etc) do a LOT of sanding, fix or fill the dents, sand some more. spray the car with primer, sand again. paint the car, hope it comes out ok since you've never done it before, then possibly sand and repaint again (probably at least once, since it's your first time), then reassemble the car.