Help me live up to who I want to be and get my life together

I'm preparing for jee,I'm in 11th grade. I'm 16. I was one of the most curious children I know. Whether it was nature,science,politics,history,I gobbled knowledge up for fun. But my dad had severe bipolar disorder,resulting in my parents getting divorced when I was 3. My mom used to beat me a lot as a child and never supported my interests. A friend of hers who used to take me cycling drowned when I was 10. When I was 7,I discovered a sexual relationship between my mom and a friend of hers,hes married,with 2 kids,and is ten years younger than her. He stays with us sometimes,and he and My mom used to berate me over my interests as a child.,My grandmother took care of me and was my best friend. I watched her die in the ICU at 13. When I was in 9th I was put on lithium. Now I'm on ritalin. Now I'm just rotting. I am stagnating so hard it's crazy. I fill my brain with useless junk dopamine by doomscrolling instead of picking up my books. Maybe I'm scared because lots of people had expectations of me as a child and as a teenager,but because I was dealing with so much shit,I was really immature and never could live up to them. Now I'm paralysed by fear. I have so many ideas about physics,and so many books I want to read,so much knowledge I want to consume,but I just can't. I literally just AVOID even sitting at my desk. And it's so sad because this is the ONE thing I've ever wanted : a shot at a university where my thinking is SUPPORTED. Like if you gave me the opportunity to have anything ever in the world,I'd choose the technical ability to express my physics ideas. AND ITS ATTAINABLE,LIKE ITS LITERALLY ATTAINABLE FOR ANYONE WHO PUTS IN THE EFFORT,BUT IM NOT EVEN TRYING WHY? I DONW KNOW.But I'm just throwing it all away. I'm outperformed by everyone I know. My dopamine baseline is screwed. My self esteem is utterly crushed. For the last 3 years or so I've been a clown. Like I mean an actual jester - I'm really funny but that's all I've done these past few years. Literally just go to school,act like a crazy maniac,make people laugh,piss off teachers who have yelled at me for "wasting my potential" and then come home and ignore the silent crushing reality of my own mediocrity by drowning myself in social media and irrelevant tv shows. Please help me get my crap together. Please tell me how to lose myself in what I want. What I need. What I always wanted. What I'm passionate about,and how to excise this fear from it.