Greetings!

You didn't have biology initially but now you want to repeat with biology as a subject through NIOS and it wouldn't be a problem at all to pass your 12th standard with biology as a subject. But you might face some problems, if you will appear for neet or any such exam and you want to get into a government college, there at time of documentation it may create problems but if you go for private college there won't be any such issues and if you are planning studying overseas you have to complete 11th and 12th both with biology as a subject, so before you opt for that make sure you have all of this in your mind.

I hope this was helpful.  Thank you!