Hello !
Being a Biology student,you have a lot of options to choose a suitable career.
Here are few courses or lines you can choose as a Biology student :-
1.Medical Sciences -Being a Biology student,you can opt for medical sciences.
You have to appear NEET to become a doctor.
2.BSc in Biological Sciences- You can choose BSc with Botany/Zoology/Biotechnology courses as honors.
Some of the best colleges to purse BSc with Biology are
i.University of Delhi
ii.BHU
iii.Utkal University,Odisha
iv.Ravenshaw Univeristy,Odisha
V.OUAT,Odisha
VI.Rama Devi Women's University,Odisha

3.ICAR- You can apply for ICAR UG entrance exam. ICAR is one of the best platforms for Biology students to pursue their careers in Agriculture and allied Sciences.ICAR hosts multiple number of colleges throughout India.Out of which IARI,BHU and OUAT are the best institutions.

4.NISER- This is a research institute for various disciples.Biology is a popular branch in NISER. You have to appear NEST to get a seat in one of the NISERs.

Hope this helps !

Dear Sir/Ma'm, after class 12, there us no such thing as course in medical field. There is this medical course as a whole of 4.5 years after completing which you can decide in which field you will do specialisation. For pursuing medical, you need to sit for the National Eligibility cum Entrance Test which is held every year for admission to various medical colleges all across India. You have to qualify it with a score of atleast 470+ in order to secure your place in any good medical college.