sir i will give class 12 thrugh nios in april 2020,its results will decleared at june its meant i am not eligable for jee advance?

Hello,
JEE advanced will be conducted on 17th May, 2020.You must have completed 10+2 at the time of counselling which means that you must obtain your 12th certificate by 3rd week of June, 2020 as the counseling will start from 3rd week of June,2020.
Candidates who are appearing in 10+2 in the year 2020 are eligible and a candidate must have passed 10+2 with atleast 75% aggregate and for SC/ST/PWD it's 65% aggregate from a recognised board or university.
And a candidate must have qualify JEE main
So check the above eligibility criteria whether you are fulfilling it or not.