Indian Institute of Science Bangalore Answered Questions

For joining IISC, there are two choices :-
1) After completing 12th Science
2) After completing B.Sc. 1) You can join IISC after 12th by giving JEE entrance exam or an entrance exam conducted by IISC for an admission in BS or BS+MS programme offer by IISC.
2) You can join IISC after completing B.Sc. By giving IIT JAM entrance exam for an admission in Integrated Ph.D. courses.

Most institutes offering the course admit students based on their performance in a relevant entrance test followed by a round of Personal Interview. Admission process generally varies across colleges.
Candidates are selected based on performance in the Research Eligibility Test (RET) and interview conducted by a given institute.
Candidates who have already qualified UGC/ CSIR (JRF)/ NET/ GATE/ M.Phil./ M.Tech., or equivalent examinations, are not required to appear for the Ph.D. entrance test, but need to appear for the round of Personal Interview.
Some of the top institutes in India which conduct entrance tests for admission to the course are:
University of CalcuttaAgra UniversityOsmania University

Hello Shanu,
You can appear for IIT JAM Bio technology examination. The IIT JAM exam is a national level exam, which is held for the admission into IITs, or IISc institutes for M.Sc. M.Sc-PhD and other integrated courses. IIT JAM Exam is held for six subjects physics, mathematics, geology, chemistry, mathematical statistics and bio-technology subjects. The candidates must have completed the graduation degree in that subject for minimum 4 sem or 2 years. As you have completed the B.Sc. In Bio tech, you should apply for IIT JAM Bio technology subject, Make sure that you fulfill all the eligibility criteria for the exam from official website.

Dear Virat,
Your salary will be determined by your grades and employability. Always remember that an institute will never guarantee a job. IIT and IISC are India's most reputed and offers campus placements. A degree from them has value over the world. Universities overseas don't provide placements, what they have is career service and networking with companies. In either case, you must crack the interview.University of Auckland is quite reputed however if you get through IIT you need not worry.
Regards

Yes sure. All you need to do is cracking and ranking very good in GATE(cse). But I will suggest that it will be better if you can continue with mechanical engineering in M. E. because your plan of suddenly switching your stream from core to noncore might backfire .