Hello Sahil,

Sad to hear that due to Covid your 12th Board percentage got decreased to 60%. But you can increase your marks by giving NIOS .

For JEE MAINS, a student must have to score 75% or above in his/her 12th Board which must have Physics, Chemistry, Maths and English as an additional mandatory subject.

To increase your percentage, you can definitely repeat your Class 12th by giving NIOS examination. If you want to give exam for only one subject then the marks of rest of the subjects will be automatically added to your newly generated marksheet of NIOS.

So, coming back to your question, YES , you can definitely increase your percentage to 75% and above if you study well for it and give NIOS examination of 12th Class. Furthermore, the newly generated 12th Marksheet will not at all interfere with your JEE MAINS & IIT-ADVANCED exams if you score minimum of 75% in your NIOS 12th repeat exam .

You can read an article on NIOS by Careers360 here :-

https://school.careers360.com/exams/nios-class-12/amp

You can check your result and your Rank for JEE MAINS using this link :-

https://ntaresults.nic.in/resultservices/JEEMAIN-auth-22

You can predict your college using this link :-

https://engineering.careers360.com/jee-main-college-predictor?utm_source=qna&utm_medium=jee_cp

Hope this helps. All the Best.

Thank You.