As per the latest NEET eligibility criteria if you have passed or appearing for 10+2 or equivalent with Physics, Chemistry, Biology/Biotechnology and English as core subjects from a recognized board or even from NIOS and the class 12th percentage to be considered are aggregate marks only for PCB subjects which is :-
- UR - 50%,
- OBC/SC/ST - 40%,
- PWD - 45%
So if you if you are studying through NIOS then also you are eligible for NEET.
For complete details about NEET eligibility criteria kindly check out the link given below :-
I hope this information helps you.