How should I approach girls (really bad case)?

hello everyone, im an 18 years old guy and my socializing skills are extremely bad.

I've been isolating my self for the past 4 years, started being depressed about me not being able to get certain things done, been doing drugs and tried to overdose on high amounts of xanax and alcohol a few times. now my parents look at me like im a degenerate (which i probably am at this point).

the overdose attempts were almost always because of feeling guilty, madness, feeling alone and a failure overall.

the only two times i dated a girl i just couldnt handle it, not that i would be a crazy mf, but i just wouldn't know what to say, like a few sentences and that would be it, she tried to keep the convo up but i just wasn't able to. the feeling i had everytime i got back home from these dates was just sadness and feeling worried about what she wouldve thought about this.

I've had a few other similar situations at school, i had two crushes, and they actually looked to be interested in me, one of them was really flirty with me, the other even told me she liked me in a stealthy way, but once again i couldnt handle it, i was afraid that i misunderstood something. And even if a girl is flirty with me, what should i say? i just dont get it, i feel like i cringe my self for anything that comes out of my mouth in these situations. i just wish i could fix my self.

how do i look? im 1.95cm (6.4 i believe in feet) tall, blonde hair (mid/long), skinny

what are my interests? i love software development, but guess what! i can't even do that now because everything i create i just think is dogsh*t if its not perfect, i dont even have patience with my self! what a wonderful life. (everythings in my head but i can't produce it)

insecurities? i need to remove a few scars because of the acne i had, i have no friends.

sorry for the long "additional details", i tried to synthesize this whole thing a few times, this is the best i couldve done.

any advice is fine, thank y'all.

How should I approach girls (really bad case)?
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