I can't figure out what to do in the first screen.
Thanks for taking the time to check out my game! If you're talking about the very first screen, you can move your character around with wasd and when you get near an interactive object a button prompt should be displayed. To start the game just walk up to the "new game" teleporter and press E. If you were talking about the first level though you need to pick up and place the towernext to the power beam (by pressing E again) to activate the teleporter to the next level. Hope that helps!