Well I would recommend you to opt for NIOS.

The curriculum is alomst same with an added advantage you would not be going to school.

This will have immense benifits concerning your preparations for AIIMS/NEET as you would be having only one year.

I would recommeng you to join a coaching institute having fair reputation in medical entrance examinations. As by joining a coaching institute will provide a discipline at your preparations.

All the best for your future endeavours