Hey! Congrats on losing those 66 pounds! That's great!
Don't be too nervous. You'll go into the meeting and sign up. Then they'll have you weigh-in and give you a bunch of materials.
There will be a meeting, and after the meeting you sit down with the leader to go over exactly how the program works.
Your first week you'll just be learning how to count points and keep track of things. It's not at all difficult. If you have any questions you can ask your leader or post here. There are plenty of WW members who've been at this for a bit so we might be able to lend a hand with certain questions.
You'll be fine. Go and have fun!