What things should I know going into a Methadone Clinic?

What things should I know going into a Methadone Clinic?
For example:
I am on Oregon Health plan. So I asked the lady at the front desk, when I was there for my initial visit, if they take Oregon health plan. She said, “only the county one does, but if you pay cash here for a while we can get them to cover you here eventually.” So, in my first intake by my worker I asked, “I have Oregon health plan, the lady at the front desk said that if I stay here for a while that oregon health plan will start to cover me here.” Big mistake! She then said “Oh I wish you hadn’t just told me that because if you have OHP that means you should have been sent to the county one.” Then I said “well I’m not really sure if I am on it or not actually because I always end up having to pay for office visits and I don’t have a PCP.” That was the only thing that saved me from having to go to the county one. I’m not going to get into why the county one is bad and why I want to avoid it. Anyway, I could have saved myself alot of greif by just asking you people on here. Everyone on here is always so helpful. So please, if there is anything you can tell me that I need to know about entering into a Methadone Clinic for the first time, then please tell me. Thank you so so much ! !