Here's what happened at mine: I sat down with the doc, she took a history, and then we talked about what my goals were -- did I want to masculinize as fully as possible, or did I want to look more androgynous? She went over what to expect from T, the possible side effects, the options for taking it, etc. Then she did a physical exam: took my BP, listened to my heart/lungs, tested my reflexes, etc.
She told me to go get a pap smear done (I had a mammogram while I was at it -- I'm older), and she put in an order for a bunch of blood work.
She called me a week or so later, went over the results of the lab work (and nagged me about the pap smear!

), and we talked what needed to happen next; my cholesterol was a tad high, and she wanted to get it lower before I started T. That held things up for about a month; then I saw her again and she wrote the prescription for T.
It was all very straightforward, and I've been very happy with the way she's treated me since.
I gather that some docs do pelvic and breast exams as part of that first appointment, so that would be something to be prepared for, dysphoria-wise. It wouldn't hurt to ask about that if it's an issue.
I don't know where you are in this process, of course -- if you've seen a therapist, or need to. If your first appointment will be with a therapist rather than an M.D., just know that they
are on your side -- the goal is to help you figure out what's right for you, not to be a "gatekeeper." Just be honest, and you'll be fine.