As for Osmania University the eligibility criteria for B.Sc is as below:

Clear 10+2 Examination from a recognized institution with an aggregate of 40%marks (pass percentage for SC &ST candidates) in the concerned Science subjects i.e, Physical Sciences & Mathematics group OR Physical Sciences & Biological Sciences.

Admission will be given on the basis of marks obtained by the student in the 10+2 examination. Students will be selected for direct admission provided they must satisfy the desired eligibility criteria.

Submission & Registration of Online Application Forms for PG Courses in Nizam College is 23 Apr - 01 Jun, 2020

And Entrance Exam dates (OUCET 2020) is 04 Jun - 13 Jun, 2020

Best of Luck!