Hello Uday

Since you are a science graduate of biology stream , you can not enroll in medical graduation on the basis of this B.Sc. If you really want to be doctor then you only take entrance exams on the basis of your 12th class not BSc. Now you can try only for MSc course so as to be in medical line.

After qualifying B.Sc. degree in Botany, Zoology, and Chemistry  there are a lot of courses you can pursue. You can go for Master’s degree in the following streams :
M.Sc. in Biochemistry
M.Sc. in Bioinformatics
M.Sc. in Biotechnology
M.Sc. in Microbiology
M.Sc. in Genetics
M.Sc. in Zoology
MBA in Biotechnology
MBA in Pharmaceutical Management
You can also go for a degree in Environmental Science, Industrial Fish and Fisheries to contribute to the benefit of nature. The environmental science has a great scope nowadays due to the increasing threats to environment such as global warming pollution and many more.

Thank you