getting nowhere in life, am i gonna be like this my whole life or not

i dont know what to do with my life, i'm 21 and im a shut-in,socially awkward even really scared about going outside (even to the grocery store) , when i talk to someone even online i get fucking nervous and awkward, i feel like people are staring at me constantly and judging me at school (yes i still go cause belgium special school stuff), everyone in my friend group has a better life than me i think the last time i made a real friend was back in 2018 and i was 12, and i'm jealous of other people but i know i shouldn't be, trying to be a good person every day i love helping people especially older people since they are very nice usually and trying to make friends too but i always end up shying away and just blocking them on everything cause i'm too scared to talk to someone and it just drains me, other than school rarely go outside cant even talk to my mom cause she never gets me, cant talk to my dad either (reasons) only person i can talk to is my sister bcuz she has autism too and were both into anime and other stuff, not seeking sympathy just lost tbh i'm sorry for being cringe but i feel like im going nowhere