M.Tech

M.Tech seats are filled only through GATE exam.

Hello Saptrishi,
To be considered for admissions, you must take the GRE, a score of 300 and above is usually considered good. You should also take the TOEFL. The application process is online, details will be found on the university website. Universities in USA takes a holistic approach towards admission, so they will not only evaluate your scores but also your extracurricular, project work, internship, publications, etc. Reference letters, statement of interest will also be considered. Always apply early.
All the best.

Stipend is given for internships only.

Biotechnology is a rapidly developing field. Many private businesses are exploring this field and heavily investing in it. It is safe to say that there are ample of job opportunities for M.E./M.Tech biotechnology graduates in private sector. Government sector too offers job opportunities, but not in the scale in which private sector does. Average starting salary is generally between 2.4 to 5 lakhs rupees per year.

Most institutes state minimum eligibility to be an undergraduate B.Tech degree in Chemical Engineering. - The Indian Institutes of Technology have the added eligibility criteria of a valid GATE score, which is only relaxed for those who have obtained their B.Tech from an IIT with a CGPA of more than 8.0/10 as well.
Note- Some institutes allow the equivalent forms of B.Tech in Chemical Engineering, such as a B.E. in the same field.
Regards.

You can do M.Tech also by qualifying GATE exam.
After M.Tech, you can do Ph.D or a job in any company.
After B.Tech, you can MBA by qualifying exams like CAT or MAT. After that, go for a job.
If you get a good score in GATE exam above 96% then you can get a chance to get into a good college like IIT.