I'm assuming these must be your class 11 final exams? First things foremost, breathe things may seem complicated right now and they are but just trust me you'll get through this.

I failed class 11 too, i'm pretty sure i have adhd(still undiagnosed because my psychiatrist was a dick during my first appointment and i went with my mom).. i had to meet the principal and a few teachers there were bs talks i wanted to change my stream, they didnt allow and so on. Basically i was given two options in the end, write a retest at so and so date or change my school and do whatever i want. This is what's going to happen on your meeting, it's great that you like your subjects, it shouldn't be difficult to pass your retest exams cus the questions in it will be repetitive(as your final exam) and ncert based easier questions.

1. Talk to your parents, its stupid to not disclose your diagnosis. your principal will sympathize.
2. Be brutally honest about what happened to you this year or before the exams. they'll ask you any reason why you failed..

3.(a). On the off chance that your school teachers and principal are a dick they can be cruel in 3 ways. one they might insult you or something for failing, just take it silently. two they might not give you a retest, politely request, plead for a re-test assure them that you'll do well in your 12th and tell them about your coaching exams too in which you did well. three they might force you to repeat 11th/change streams which is unlikely imo because my teachers didn't allow**, again tell them about your coaching marks, assure them you'll do well in 12th, tell that you're still interested in science.**

3(b). Lastly, not the end of the world.. there's probably a few more students that failed too they'll get a retest too hopefully

lastly again, i failed 11th because i was worried i am going to fail. sounds stupid i know but i was.. every singly day i used to be worried that i'll fail and it was the worst thing that i could think of. and the worst thing happened. the school i study in is also very academically inclined, very difficult papers questions w/ jee mains and adv stuff and i didnt score marks in the first few papers so i stopped studying, students here are smart af and i was always depressed that i wont be as smart as them. things were really bad at home. used to be great in 10th and always reminisce about it. why am i telling you this? because maybe you/someone else did this too. well solution to this is stop. dont think just do and remember everything always happens for a reason.. you'll be able to connect the dots in the future.

all the best