This may be a dumb question, but what does the primary spring, it doesnt have anywhere to go. It just sits there with a cup of metal bolted down holding it in place. It doesnt even move. How does a primary spring make a difference in the clutch, what does it even do??

It is called centrifugal force.

As the clutch spins, the weights inside the clutch are pushed out. The spring sets the presure on the weights.

newf

The primary effects several things including your engagement. If you have a weak spring, you will engage at a low rpm since the weights will be forced out faster but you will shift out way too soon. If you have a very stiff spring, it will do just the opposite and engage way high. Everything has to be balanced between your weights, primary spring, and your secondary components.
Take your belt off and rev up your engine. You will see how your primary spring comes into play.

but its bolted in by a metal cup, how does it move??

The entire front part, the part that is bolted to the spring, it all moves together. Pull your belt, or put it on a stand and rev it up. You will be able to see what we mean...