I just really need to know , I mean I'll be standing in a group of friends and one person suddenly stands in the middle of the circle with her back facing me?
Also another girl make me look stupid all the time and say things like
Me- its quite quiet
Girl- obv its quiet nones in yet! (snapping at me)
This girl snaps at me all the time , she never listens to me and whenever I say anything she always tried to turn it into an aggression.
How do I deal with this type of person?

Ignore them.

People like that like to get reactions out of you. When you ignore them, act as if they are irrelevant, they don't get the response they want and they move on to someone else.
Ignore her.