IIM

no brother there are many institution but also they charge huge fees. u can get idea from Google .

Delhi University is best

you should secure at least 50% for applying in CAT exam and for getting decent colleges

IIMs only provide management courses. There is no MBA + Sciences. After MBA you can get into research field in Biotech or medical research. Bit most probably it will change your field of career. AS Biotech and MBA are two different courses. I think M.tech in Biotechnology will help you more.

IIM admission is on the basis of CAT examination. You can not apply to any IIM on the basis of MAT results.

you should prepare for CAT entrance exam because in top IIMs you can get admission only through CAT with good percentile I.e.,above 90

Susmita what about the result (percentile) of your CAT exam. Did you give that exam? Without that you cannot get into IIM's.

Yes, you can get admission in IIM after clearing CAT/ GMAT and getting a good score in it.
To appear for CAT etc  student needs to have 50% in graduation. But eligibility criteria varies for various Management Institutes or Universities, they can take different %age in graduation along with these test. 
These days we have many other B-Schools that are at par with IIM. Many of them offer admission on basis of these tests/ their own tests/ GDPI/ marks in previous qualification.
You can check the websites of universities like Amity, Lovely, Chitkara, Manipal etc for more details.
Good luck.

Dear Shubham, you might have got the seat at IIM Sambalpur is based upon your rank. IIM-S maintain standards, you will get good placement in future. Settle down if not, try at good private business schools at Mumbai. All the best.

Top seven IIMs would call you for GDPI at 99+ percentile in CAT and same as for XLRI where cutoff same as IIMs and exam accepted is XAT. Good luck and cheers.