CBSE 10th

For graduation or taking admission to any undergraduate course, You need to pass HSC. You can try taking a certificate of class 10th and 12th from an open school. NIOS provides such things.
Explore it.
All the best.

Yes, you can study computer science Diploma in government Polytechnic College with 85.40% in class 10th board exam. The minimum eligibility criteria to apply is that a candidate must have passed class 10th examination with a minimum of 35% with mathematics and science.

Yes, you can apply for any Diploma after 10th. But for which Diploma you are asking for?

Hi,
Yes, you are eligible for giving the NEET exam. You must have studied physics, chemistry, biology and English in 12th.

Please mention the name of the college and the course that you want to pursue.

You have not mentioned about which course you are seeking for admission in IIM Ranchi as every course has different eligibility criteria.

Hi,
You can check out the below link for all MBA colleges all over India. However, if you want to know about a particular specialisation or region wise MBA colleges then do comment.
https://www.shiksha.com/mba/ranking/top-mba-colleges-in-india/2-2-0-0-0

Yes, you can easily do Diploma in microelectronics after 10th or after 12th also.

Yes, you can join this course.

Yes, you are eligible but first, you have to give polytechnic exam for the admission.