Good adice above, I am not certified, but do a lot of successful electric work.
It is easer to think of electric like plumbing. Black (hot) is the high pressure water.. (just like a fire hose). A switch is simply a valve to turn the water on and off. The current goes in one side of the device and goes out the other side on the white (drain). It can also just go out the ground (messy just like a bad drain).
Paralel man! Series and you get dim bulbs! Take a deep breath do it and you will soon understand not as complicated as it might seem.
Green wire... use it. connect all the green wires together to the ground circuit, ground the metal frame to this if your project is metal. I know some old codgers will tell you you don't need no stinking ground. I like the idea, and think it can save you some pain or death.