Colleges in Kolkata

Eligibility criteria:
Students with 60% aggregate marks (or an equivalent grade point average) in Bachelors degree in any branch of Science, Engineering, or Medicine are eligible to be apply for admission. Students from the SC, ST, OBC (non-creamy layer), and PWD categories shall be given a relaxation of 5% marks.

Yes, you are eligible for Masters Degree in Social Work.
A candidate who has passed B.S.W. / B.A. degree examination fromunder a recognised university can see MSW admission. A candidate who has secured minimum of 50% aggregate marks in B.S.W. / B.A. degree under a recognised university has the required MSW course eligibility.

You have to clear all the subjects only then you will be able to pursue M.com.

Techno India University offers Integrated M.Sc-Ph.D in Microbiology. It is a 5 years intensive programme for students who have cleared full-time B.Sc. Or its equivalent examination.

Amity University, Kolkata offers courses in the fields of Engineering, Management, Commerce, Science, Arts and Law. The fee structure for the courses are mentioned below:
The course fee for B.Tech range from INR 84,500 per annum to INR 10,05,00 per annum.The fee structure for M.Sc ranges from INR 38,000 per annum to INR 55,000 per annum.The course fee for M.Tech is INR 79,000 per annum.

You need to complete class 12th first for this course.
B.Sc in Hotel Management is a 3-year full-time undergraduate course, the minimum eligibility for which is a Higher Secondary Certificate (10+2 qualification) with a minimum aggregate score of 50% in best four relevant subjects.

Yes, it is compulsory, if you want to get admission into B.Com in St. Xavier's College.

The fee is around Rs. 2,400 per year.

That is something the college authorities may ask you at the time of admission.