Hey there, bluekitty04! I'm a shy one too. Not fun.
I took some detours in my life's path after high school and I ended up majoring in theater in college. That's where I found a way out or around my shyness. Being a theater major, I had to take an acting class AND be in a play.
AKK!!
But as it happened, in spite of terminal stage fright (that's an actor's term for shyness), I got my degree.
It's like jumping in the swimming pool, "feet first" as Raindropvampire says, when you walk on stage--or into a room of strangers, or your classmates are in happy little groups, having lunch & none waiting for you to join them. And IceCreamKid outlines a good script. Look around at the other kids in your class. Is there somebody else who isn't connected?
By giving you a script, IceCreamKid has given you focus. That's the key!
When you go into the room, you know what you're going to say (more or less), and you know where you're going--who you're going to talk to, the other character.
So you're not really jumping into the pool, risking death by drowning!! You're not making a fool of yourself--you don't panic. I have a coworker who puts her hand in front of her mouth and is trying to break herself of that; she says she does it because she feels like she should stop talking most of the time. Her husband is always telling her she says stupid things. I looked on your profile page and saw that your brothers bully you a lot. Maybe that relates to why you cover your mouth when you talk. I don't know--you'd have to talk to a therapist about that.
This acting approach feels really phony, at least it did to me at first--& it still does. Oh yes, I still have to "fake it till I make it"! So do a lot of veteran performers. Terminal stage fright, or shyness, is part of the human condition. Working on it is no more difficult than being shy is, but the payoff--I promise you--is a lot better.
Take best care of you, bluekitty.
Roadie