Need some socialzing advice?

well i guess im what you might call "socially awkward":[. i have a lot of friends, but now im in high school and we are all seperated..i am extremely bashful and i have a hard time talkin to the older kids cause i really dont want to say the wrong things and look like a compleet loser..and i dont really have much to say a lot of the time. how can i learn to come out of my shell and be confident? thanks yall :))