Colleges in Pilani

BITS takes conducts the entrance test online for M.Tech. So, previous year papers are not available for practice, but you can take help from the samples papers available both offline and online for M.Tech entrance exam conducted by BITS. There are two papers, one includes English and maths second is your core branch paper.
So, you could practice from the above sources. Apart from it, if you are also preparing for GATE then the pattern is almost similar for respective branches which include both aptitude test type questions and core engineering questions.

http://www.bitsadmission.com/bitsat/BITSAt_2017_Brochure.pdf
Check this link for BITSAT syllabi.

http://bitsadmission.com/cutoffscores.aspx
Check this link for BITSAT cut off scores:
http://bitsadmission.com/fdmain.aspx

BITS, Pilani is better option than CSE.

http://bitsadmission.com/hdmain.aspx
Check this link.

BITS-Pilani offers general MBA programme and not specialisations.

Check this link:
http://www.bioconacademy.com/program_overviewmicrobiology.aspx

Go through the link to know about the details: http://www.bits-pilani.ac.in/university/wilp/wilpoverview.