Science

Yes, the college requires 50% marks in class 12th with Mathematics. The admission will be based on entrance test results followed by counselling.

Here are the list of colleges which doesn't need Maths, as a requirement. Christ University, Bangalore
Symbiosis Institute of Computer Studies and Research, Pune
Institute of Management Studies, Noida
Lovely Professional University, Jalandhar
Sikkim Manipal University
Manipal University, Jaipur
St. Xeviers College, Jaipur
Poornima University, Jaipur.

The universities offer migrations into same course and changing from regular to distance in generally not allowed. at first you should confirm if migrations are allowed or not in Bharathiar University from DU. you should contact the Bharathiar University to know about the process of migration.

It has a great scope in Canada as:
Salary. Microbiologists at an entry level position make between$34,000and$47,000per years in Canada. With several years of education and experience, microbiologist make between$48,000and$78,500per years.

https://www.shiksha.com/science/iit-jam-exam
Hope it helps you well.

The fee for B.Sc in NPGC is Rs. 19,998.

HII.
YESS you can join after B.sc in physics you have to give bitsat exam for MSC .

Hii. Yess you have a chance. Here you can go and check his website for your doubt. https://www.shiksha.-unversity.