MCA Eligibility

GRE and IELTS are both popular requirements for any form of study you wish to pursue along with the additional work experience that may be required. If you believe you're falling short on the experience front, my best suggestion to you would be to enroll yourself in a form of study which would then allow you to scale up to a PR and a job opportunity in Canada. One of the interesting one's that I recently encountered is this Study & Work programme where you basically get to do a course while earning part-time and once you finish the course, you can work full time for about 6 months.

Yes they are eligible.

There is no as such minimum rank. But try to score in the region of 95+ percentile in CAT to have a good shot at the IIMs and other government colleges like FMS, DFS, DBE. All the best
The candidate must have passed Graduation in BCA or equivalent from a recognized board. The candidate must have acquired a minimum aggregate of 60% in the qualifying examination. The candidates who are in their final year of degree can also apply for admission.