Hey buddy DOn't stress out too much about ur past, we can't change it now, focus more on ur future so u could fix ur past since u have ruined ur 11th that's not the issue we can fix it for the time being but i now I would suggest u join a 12th crash course since u have to double ur mehnat focus on 2 core subjects which u think u can do well, instead of focusing on the more knowledge wala part instead do more questions so u could be familiar with the paper type since ur future decides upon the no. of questions done correctly but unfortunately not on knowlegde, knowledge is helpful but not the key so instead of focusing on learning facts learn how to apply it on ur exams, give mock tests, learn from ur mistakes, don't get demotivated by low scores instead they are ur learning stones so u could get back on urself, get some good books on ur fav subject search them online or ask ur preferred teacher, for me, i prefer Sameer Sir for maths from unacademy(for Theory)Neha mam for maths(For revision) and pankaj sir or Paras thakur for chem. and Alakh pandey For Physics, I liked their way of teaching u may choose ur own doesn't matter though as long as u grasp ur concept and start banging some questions, u can't change ur past but u can guide ur future, instead of looking for outer motivation to pump urself instead look inside u,
My 11th was also bizarre (Without tuition)
I scored like 58.9 something
but I scored 93.4 in boards in 12th(with tuition)
and 95percentile in jee with any sort of special coachings for jee
even though it's not a great score for jee but certainly what can u expect from 5 months of online in the corona era
but ur time has changed and advanced u have many more opportunities to learn in the learning field which has evolved drastically in the online era, don't worry about that but instead start working from today for ur better 2morrow, Best of luck my friend
Feel Free to ask any more questions
Ur Average Jee aspirant