I assume you’re talking about that funky Old-Skool dryer in Module 3, unit 2. Don’t feel embarrassed! Despite being old technology, these kinds of machines can have some of the toughest circuits to puzzle out.
First things first: rewatch the video in that unit. The Samurai spends a lot of time covering your exact question in that video. If his explanation still isn’t clear after rewatching it, write me back, and I’ll try to break it down further.