NIOS 12 th

Hello Rajdeep,
Yes, you can go for NIOS board in class 12th or you may go for admission in distance learning program offered by many colleges such as IGNOU.
All the best.

Yes, you are eligible for that. But you are advised to clear B.Ed also, so that you can try for high school and higher secondary in future.

Yes, NIOS students are eligible for MBBS.

No, it will not be possible as there is no engineering college/university in which session begins in the month of December or January, for details check the link below:
https://www.shiksha.com/b-tech/course/b-tech-in-agricultural-engineering-mahatma-jyoti-rao-phoole-university-jaipur-201809

Hi Sajid, check out colleges and institutes and the eligibility here and apply:
https://www.shiksha.com/engineering/colleges/diploma-courses-india

Hello Jaiveer,
Of course you are eligible. NIOS is government recognized and this recognition is acceptable to all.

Hi Vishal, many universities accept NIOS and many don't but it is difficult to point out any names. You have to contact some colleges abroad, visit college websites randomly and email them. They will reply and guide you accordingly. A lot will depend on your profile. All the best.