dont worry bout all that stuff bro. just start with hi and a smile dont worry bout all the other stuff in the beggining itl just overwhelm you if you dont take baby steps. i think i speak for a good majority of us that wev all been there and most of us if not all have gotten over it. ud be surprised by what a friendly smile and a hi will do. once you can do that comfortably then start working your way up and learn from your mistakes and from ours to and everything will start to work for you.
good luck
oh and dont be afraid to ask questions lol