Hello Aspirant,

Hope you are doing good. According to your question, you've failed in 11th and then graduated from NIOS instead of continuing with CBSE. So, that should not be a problem. Students who have successfully completed Senior Secondary Examination of NIOS are eligible to appear for NEET(Under Graduate) Examinations.

However, if you haven't completed your 11th and 12th at all, then unfortunately, you are not eligible to take NEET. As per NEET guidelines you must have passed in class 12 either in regular classroom or in open school,

Hope this helps.