Hi,
I'm quite shy in some circumstances. Definitely, in groups, I am not comfortable in groups at all, I almost seize up. But one on one, especially if I know them somewhat and like them, then I am much more relaxed and open and can chat loads, I like one on one situations. It all came from my school years, got picked on, then later just rejected. Used to just hang around groups of kids on the outside and not say anything, just hoping to be invisible to not become prey. Blamed bullying for my shyness, and of course thats a big part, but as I get older I tend to put more thought into thinking how I was seen by others... probably somewhat autistically shy and a bit odd I guess, and maybe I had more responsibilty than I thought at the time. Im gonna assume you are fed up with being shy... well, if so, I think you need to practice socialising more, in the areas you want to and need to. Jordan Peterson has talked about this, volontarily putting yourself in those situations to help you overcome them.
I'm incredibly shy around girls, probably that's when I'm most shy, again down to the rejection issues. I did the whole online dating thing a few years ago, did maybe 20 dates, couldnt get over the shyness, couldnt relax, things didnt get better and I relised this wasnt gonna work for me. never got a 2nd date, but funnily enough, as soon as it became apparant there was no other date, BOOM, pressure off, I could talk to the girl, relax and be myself.
Anyway, tell us more... if you want more help