Dear Shuvro, if you appear only for Biology through NIOS, then you will not be eligible for NEET. But if you  study Physics, Chemistry and Biology/Biotechnology again, you are eligible for NEET. And please remember that you need to score an aggregate of 50% in these 3 subjects to be qualified for NEET. It is 50% for General Category, 45% for PWD and 40% for OBC,SC,ST.

Dear student, 

You have many options with pcm and trust me medical field is not that easy . There are students who take a combination of pcmb because it's literally very uncertain in medical line . The competition is way too much tough and there are lots of students fightufi for the fee seats that are available for MBBS and BDS . Although if do your 12th again with PCB then you can appera and give neet . But students who prepare for NEET they prepare from way to earlier because as I told you about the competition. I hope this was helpful