Science

Let's be frank that is for M.Sc currently the college is facing in placements issue, so it is somewhat difficult to get job.

There are books available under different authors like Venkat Rao, Payal Bhola Jain and Shubra Mangal for B.Ed Pedagogy of Physical sciences, but if you are from Hyderabad or visiting Hyderabad, go to a bookstore called Shraddha Book Depot. There you may get hands on different varieties of books for your entrance exam.

I would suggest you to pursue Masters like M.Sc in the same subject or relevant ones.

CS in UPES is better as in UPES we have 95% placement for CS students and faculty is very good.

As there is a huge competition for this college it will take some time. To get information from them. So, wait for it and proceed.

Yes, you can, there are a variety of Specializations you can enroll into, but see if you want to have a MBA within your supporting background of Life sciences (which is highly not possible), but possibly something new like:
General Management. International Management. Human Resource management. Consulting. Finance
Entrepreneurship. Operations Management etc. There are some PGDM colleges which even let you have Dual or triple Specialization.

You can get it from Jamia Xerox Point.