CBSE 12th

It will be decided by you and your interest that which field attracts you or which subjects are of your interest.

Hello Chanchal,
Here are a few courses for you:
MBBS
BAMS
BHMS
BUMS
BDS
Bachelor of veterinary science and animal husbandry
Bachelor of naturopathy and yogic science
Bachelor of physiotherapy
B.Sc in nursing
B.Sc in dairy technology
B.Pharm
Biotechnology
BOTgeneral nursing
BMLT
Paramedical courses
And many more even you can do engineering.
Best of luck

There are many courses available for you like:
Computer Science engineering.
Mechanical engineering.
Civil engineering
IT
Architecture and many more. It depends on your interest.
But for engineering, you have to crack JEE Mains and JEE Advanced and for architecture, you have to pass NATA exam. So, best of luck.

To do B.Sc in maths, you need at least 55% in maths in class 12th.

DU has a wide variety of UG courses available. First of all you have not mentioned your stream so it will be difficult to give all the details. Admissions are done on the basis of 12th results. Top DU colleges have cutoff nearing 97% and there are other good colleges as well accepting 88%. I would suggest not depending on DU alone, keep IPU and JMI as options too.

There are UG courses available in many colleges, IIT being the main.
Here is the list of top colleges offering this course. Please go through each one separately to know the details.
https://www.shiksha.com/b-tech/ranking/top-aeronautical-engineering-colleges-in-india/49-2-0-0-0

See, firstly, your scores in class 10 and class 11 need to be really good to be eligible for science stream. But secondly, all depends on school admissions to take the final call. Discuss this matter with school authorities.
This is a very riskydecision as without studying sciencec n class 11 - it is difficult to score well in class 12. And if you think you are not comfortable with commerce you can think about shifting to humanities.

Hi,
If one has interest in a particular subject then it becomes easy to score. Discuss with him on his interest areas.
If he has interest in computers he can study BCA or BCS. This fetch him good job after BCA. Later MCA will further enhance his portfolio for getting job.
He can also do BBA finance and later MBA finance.
If he has interest in accounting he can go for CA.

Hello Abhishek,
Yes, 12th marks have the same important as for IIT. You must score more than 75% in your 12th board exams to get admission even in NITs. Also, if not, you are not eligible for admission in NITs.
All the best.

After 12th there are many short courses available for 6-12 months. But these courses are just certified courses and are not valid to get good jobs. So, I would suggest going for undergraduate course in the subject of your choice. Rest is your choice.