That's a question that everyone asks--it is confusing when you've never heard it used regarding food.
To be abstinent in OA generally means that you don't eat between planned meals, and you don't eat the foods that trigger your binges. However, each person has to determine their own personal definition of abstinence. Not everyone's is the same. You determine what you need to be abstinent from in order to not binge.
Abstinence and your food plan are two different things. But, you determine what both of them are and use them as tools.
I'm glad that you found this site too. You are helping me think through this stuff!
It's normal and reasonable to be shy about asking questions in the beginning. I didn't say anything to anyone the first 4 meetings. Take your time. This isn't a race, there's no rush. Learn as you go. Your heart will tell you when it's time to ask questions at a meeting.