B.Sc. (Hons)

Career Opportunities after Higher studies in Chemistry:Analytical Chemist. Biomedical Chemist. Quality Controller. Safety Health and Environment Specialist. Teacher. Chemical engineering Associate. Industrial Research Scientist. Lab Chemist.

https://www.shiksha.com/science/colleges/b-sc-agriculture-colleges-india
Here is the list of the top B.Sc. Agriculture along with their admission procedure, you can hit the link to know all the details.

Right now, you have to focus on your 12th marks and they should be above 90%, then only you can crack any reputed college.

B.Sc Hons in Physics may the best option for you, because Hons degree indicate superior academic performance over ordinary degree. B.Sc Hons Physics is a subject specific degree and have great scope in teaching, scientific and research department. Hence, my choice is B.Sc Hons Physics.

Yes, you can get admission in Amity University with this percentage. Good luck.

Yes, you can definitely apply for the M.Sc in biomedical science after doing B.Sc in medical Biotechnology if you wish to pursue the same.

This Indian Board of Alternative Medicine should be best avoided. Apparently due to police action, it has suspended all operations. I am attaching a link that will explain.
https://www.altmedworld.net/