Admittedly, it can be a bit daunting to try to get involved in the story sometimes when you PC your first event... especially if you haven't written a background for your character. (Hint: write a background. If nothing else, it gives you more flesh to the character than the bones of the character sheet.)
However, whether you PC or NPC your first event, if you need help understanding a rule, you shouldn't hesitate to ask, "what does that do?" There's nothing wrong with it, and folks will generally give you a quick description so you can react appropriately.
That said, NPCing your first event is a
great way to get your head around the rules without any of the worries that come with playing a character (such as costume, weapons, etc.) Monster camp will never turn down more NPCs, even new ones.
Now, NPCing can be just as hard as PCing, just in a different way. You end up getting run around a bit ragged, but it's usually worth it at the end of the weekend when you hear other players talking about the cool things that happened that you helped
make happen.
Ultimately, it's up to you which you decide to do, but I'd like to reiterate that, regardless of whether you PC or NPC, no one's going to get mad at you for not knowing the rules your first game out. People will want you to have as much fun as they are, and will do their best to help that happen.
The rulebook is pretty straight forward on I'd say 90% of the rules. (The other 10% is open to debate/waiting for official ruling from the Alliance Rules Committee.) I'd recommend at least getting the digital copy and reading it over before attending a game. There's a lot to assimilate in it and if you show up at your first game even knowing a third of the rules you'll be fairly well ready to just start playing.
If you have any more questions, by all means, keep asking.