Hi LW
To get selectee for the Undergraduate Bachelor's in Science or Post graduate Master's in Science you will have to answer their entrance exam first and based on that your merit list will be prepared according to your entrance marks and your 10+2 or degree marks. So your admission will be done based in the merit list and the minimum eligibility is pass in HSC or more than 50% in a bachelor's degree. For admission your link is
http://www.mponline.gov.in/portal/
Good luck