Hi Vartika

Neet 2021 eligibility criteria says that, to be eligible you must should have passed 12th board examination with physics, chemistry ,biology and English as core subjects and must have got at least 50 % in aggregate of PCB i.e Physics, Chemistry and Biology ( in theory +practical) in 12th examination if belongs to general category , or at least 40% in aggregate of PCB if belongs to Obc/ Sc /st category.

Also, the students with Biology as an additional subject are eligible for Neet examination and also nios board is accepted for neet.

But ,
it is unsure that you will be eligible by just passing your Biology later on after 12th from a different board i. e NIOS because as per eligibility criteria students who have passed their 12th board examination with biology as additional subject are eligible and additional subject is nothing but the 6th subject in your 12th board examination.

For detailed information about neet examination eligibility go through our page for which link is provided below; -

https://medicine.careers360.com/articles/neet-eligibility-criteria

So, if you want to be eligible for Neet , will suggest you to give NIOS on demand examination for 12th with all the 5 subjects including physics ,chemistry biology and English and for the 5th subject you can choose any subject of your choice like Hindi ,Sanskrit, maths or any other subject and after passing, if you fulfill the aforesaid percentage requirement in PCB then you will be eligible and can get admission in MBBS on the basis of marks obtained by you in the Neet examination .

And if you appear for 12th NIOS examination with all the five subject then you should choose the code 0 1 because it is for those who are either appearing for 12th examination with subjects including physics ,chemistry, biology, English or have appeared for 12th examination but result is awaited.

For detailed information about Neet codes refer our page the link for the same is provided below
https://medicine.careers360.com/articles/neet-qualification-codes

Thank you