CBSE 12th

Uniform academic achievement at all levels is important for a good career.

Hi,
You can ask him to go for:
B.Tech in aerospace engineering
B.Tech in IT
B.Tech in CSE
B.Tech in biotechnology
Once you have opted for engineering do not come for commerce as it would create confusion unless you have passion towards commerce else you can go for integrated MBA offered at SRM.

You can opt BBA, BBM or B.Com and try for the best colleges with decent placements.

You can do B.Sc. in gaming.

B.Tech or BE is best, if you are not interested in this, then biotechnology is also very good field. Otherwise, you can try for mathematics and computing in DTU. Engineering physics is also good.

You need to get 90% in general category.

It depends on your interest. If you are interested in humanities, you can go for that and after class 12th, you can try to crack civil services exams.
Good luck.

She can either pursue B.Sc in geology or B.Sc in earth science. This field is still in an infant stage in India, but according to experts this field will have a great scope in India in future. Geologists and earth scientists are in great demand in Australia and New Zealand. So, if she is really interested in this field, there is nothing better than becoming a geologist.

Yes, you class 12th percentage do matter, a minimum of 75% is needed to crack IIT JEE advanced. Other entrance exams do have eligibility criteria of around 60%.