How do you get the gall to actually start HRT?

I know I want to be a girl, I know I want literally every effect of estrogen and none of testosterone, and yet it feels impossible to actually make the decision. I don't have any friends so it's just my parents to judge me. Idk what I'm waiting on at this point, I'm not going to make any friends that would help with transitioning, and I'm already practicing makeup in private. The only thing I haven't done is buy fem clothes or a dress but I'm just too embarrassed to buy one at a store atp. Maybe it's just my anxiety, but I'm certain I won't live to be an adult as a guy. Any advice on actually starting?