i wish i could change everything in my life

okay so theres a lot im gonna say here. i genuiely wish everything was different in my life. im a 18M leaving highschool and my life is so beyond cooked it isnt even funny. my best friend ended his life a year ago and it completly destroyed my education, i keep telling myself that but the truth is my education was already destroyed. i want to become an aerospace engineer but ive failed 3 math classes and a physics class, i genuiely just think im fucking stupid. im gonna take a gap year and take all of the courses i need to take to get into my program (praying i can actually survive my program if i even get in) i do also have a girlfriend (same age as me) and weve been dating for years but like i genuiely am such a shitty boyfriend to her, she wants me to prompose to her but i genuiely cannot be bothered to put in the effort to plan and set this up because my highschool is just making us do so much bullshit before we graduate, all of these ceremonies and activities, oh and ontop of that we have exams and cpts too. oh and currently i have like low 80s- high 70s in easy fucking classes (i literally only have two classes right now, religion and english) i feel fucking ashamed. im also ass at literally everything outside of school too. i play a lot of video games. right now ive been playing a lot of overwatch (skip over this part if u dont play overwatch) i have 400 hours on the game (200 of which are on tracer) and ive hard deranked into fucking silver, which means a brand new player is on average ranked higher then me (been playing for years btw) and oh yeah today i also rage quit multiple rally stages on richard burns rally (20 year old game btw) so that was great oh and yea i love rally racing and card in general but i still dont have my license because im too lazy to go to driving school, i tried to make a deal with my parents to try to let me go to a school for manual cars (i want my first car to be a 2004 wrx, they only came in manual) and they basically told me its not gonna happen. im just so tired of it. i get made fun of by my friends for not having my license at 18 which honestly i cant even blame them for. oh and yea my family is also poor too so even if i get my license i probably wont have a car until im done university which i hate because literally all of my friends got there basically there dream cars from there parents (one of them drives a toyota supra) its just so humilating. your probably asking why dont i get a job? well i use to have a job. i worked at a grocery store for a year and it was genuiely one of the worst experiences of my life. my boss was a fucking bitch. i was 16 and all my co workers went at me constantly. it got so bad i almost punched one of them because they use to try to purposly piss me off. i tried applying back there after i quit but the sub manager basically told me that the manager of the department i worked in (my boss i mentioned earlier) went on a rant about how awful me and my brothers were. oh and yeah i have two older brothers who both worked 20 hours a week at my age and both have actual jobs now. i quit my job to do better in school but then i went and failed both physics and math (i took an easier math class then the program im expected to take for my degree because i knew i couldnt handle that and physics) and this was also around the time my friend ended his life. oh and right before all of that happend i got into a fight in school with these kids and i almost got suspended for it, and these other kids (not related to the ones i fought) wanted to come stab me at my work, thankfully they got arrested and moved away but before they got arrested they beat this gay kid up so badly he went to the hospital all because he was gay (im bisexual btw) and its just like dam that could of been me. so yeah now here i am, horrified im gonna be left behind after highschool, not knowing if im gonna be able to do what i want to do, and feeling completly useless and afraid. im afraid of not getting into university and becoming a bum in the future. if i fuck this up then i genuiely dont know what ill do. ive always loved aircraft and space. i want to experiment with propulsion methods for space travel (nuclear is the main one that intersts me) but i cant even pass my highschool physics class and grasp simple newtonian physics concepts. ive always been horrible at math. i have a learning disability. maybe im crazy for wanting to do this so badly. i think my main motivation now is to just prove everybody wrong and that i can do it (btw my parents and my gf all think i shouldnt go into aerospace bc i wont be able to handle it) if there right idk what ill do with my life. im sorry to whoever reads this i know its a lot, theres even more stuff thats happend over the course of my highschool but yeah idrk how id end smth like this so ill just say. im cooked.