Most people imagine a film event as something complicated. Technology, scripts, preparation. In reality, getting started is surprisingly easy.
Quick intro, then go
At the start, there's a short briefing: what's the story about? How does the shoot work? Who does what? Takes a few minutes, not an hour. After that, you're already on set.
Everyone has something to do
Acting, directing, camera, set, organizing - roles are assigned in a way that fits everyone. If you don't want to be in front of the camera, you don't have to. If you want to jump right in, you can. Nobody sits around.