The exact cutoff percentile to qualify in JEE Mains and to be eligible to give JEE Advance is not yet announced by National Testing Agency (NTA). Since JEE Mains entrance examination is again going to be conducted in April in various shifts on various days the exact cutoff percentile cannot be estimated.

I suggest you to wait for the officials to announce the precise cutoff percentile. 

If you have any other queries do mention it down in the comment section. 

Hi Aspirant

Any one can appear in JEE in april.If you are satisfied with your current score then you may leave otherwise you can take the exam.

If you are from general and with 83%ile ,you might not qualify JEE mains and will not be eligible for JEE advance.

Students scoring more than 90%ile would be in safe zone.

So you must appear again and be prepared this time.

Hope this helps.

All the best.