CBSE 12th

The duration of B.Sc in agriculture course is 3 years.

Find the best institutes for commerce coaching at https://www.hunarr.co.in/
Find the institutes of your interest. You can also join for distance education by searching at Hunarr.

Yes, you can do LLB after completing your B.Sc. in biotechnology course. Prepare for CLAT and also for the entrance exams of private college. Some colleges even give admission on merit basis also.
Don't be so stressed out. Complete your biotechnology course with good results and then join LLB in any college.
Kindly, feel free to revert.
All the best.

On this basis, you will not be able to land a good job. It's better to go for further studies.

You are seriously disadvantaged in terms of your academic performance. To get a call from IIMA, you will need to do really well in CAT. I would guess you would certainly need to get more than 99.7 percentile. Higher the percentile, better it is for you.

Hi,
For physics:- DC PANDEY is best for conceptual studies as well as for numerical.
For maths:- Cengage calculus, RD Sharma class-12
For chemistry:-
Physical: Cengage, NCERT
Organic: Solomons & Fryhle's
Inorganic: NCERT

Nowadays coaching is required for the preparation of all exams. But if you do not want to join a coaching then you should focus on what is taught in school and attend the classes regularly.
The school will prepare you for the boards. for JEE Mains you should thoroughly prepare your school syllabus of class 11&12 as the syllabus for JEE is same. You should solve previous year question papers of JEE and can also buy some books for JEE preparation. Your basics of 11th and 12th class should be clear.
All the best.

The best colleges for sciences (Forensic Science) in India are:
Department of Criminology & Forensic Science, Dr. Harisingh Gour University, Sagar
Department of Criminology, University of Madras
Department of Anthropology, Panjab University
National P. G. College Lucknow , Uttar Pradesh
Institute of Basic Science, Dr. B. R. Ambedkar University