im sorry if i offend u but i dont like how ur parents handled this, im in 11th rn and this is no way a parent should talk to their kids, demotivating them even more, taunting rather than helping them, i too kinda slacked till august (my prep started in april) bc i couldnt keep up with the teaching pattern and i had a eye procedure done, but my parents motivated me by just saying that they dont care what college i got into, that was enough to make me start studying, im not trying to make you feel worse ik what it feels like to be in ur place, my brother was in a similar situation 6yrs ago but that exp changed my parents when he spoke to them about their behavior, ur best bet is to just tell u parents what u feel, sure you will probably get a shoe thrown at u first but after some time that thought will fit into their head and they would refrain from making such comments, also u have some time for your jee, in boards u dont need extremely good marks 70% can get u into many good colleges focus on jee imo,