The basic criteria of eligibility is (10+2) or equivalent qualification with Physics, Chemistry and Biology and/ or Math as main subjects and a min score of 55%. Admission In reputed institutes is usually through entrance exam whereas in other institutes you can take direct admission. I am enlisting a few good colleges which are doing really well in this field and are known for their quality education and better placements. Top colleges are:
Gujarat Forensic Sciences University, All India Institute of Medical Sciences
Lok Nayak Jayaprakash Narayan National Institute of Criminology & Forensic Science, 
Lovely Professional University Jalandhar, 
Jawaharlal Nehru Medical College, 
Dr Bhim Rao Ambedkar University Agra, 
IFS Nagpur, Pune, Aurangabad, 
Osmania University Hyderabad.

Hello Vidushi,

Following is the list of colleges for B. Sc in forensic sciences according to their ratings (including government and private colleges) -

• TEERTHANKER MAHAVEER UNIVERSITY - [TMU], MORADABAD
• UNIVERSITY OF MUMBAI, MUMBAI
• SHARDA UNIVERSITY - [SU], GREATER NOIDA
• INDIRA GANDHI INSTITUTE OF MEDICAL SCIENCES - [IGIMS], PATNA

Good luck!

Hello,

Here is the name of the bes colleges;

1. IFS Indian Education Department, Pune.

2. Lady Hardinge Medical College, New Delhi.

3. All India Institute of Medical Sciences, New Delhi.

4. Department of Forensic Sciences (Dr. B.R. Ambedkar University), Agra.

5. Institute of Forensic Science, Mumbai.

6. Lok Nayak Jayaprakash Narayan National Institute of Criminology & Forensic Science (LNJN NICFS), New Delhi.

7. Institute of Forensic Sciences (Gujarat Forensic Sciences University), Gandhi Nagar.

8. Centre for Cyber Forensics and Information Security (University of Madras), Chennai.

9. Sam Higginbottom Institute of Agriculture, Technology and Sciences (SHIATS), Allahbad.

10. St. Xavier's College (University of Mumbai), Mumbai.

Best of luck.