Certificate

It just gives you an experience, sometimes distance course certification may not be valid everywhere.

Hello Shaikhar,
Almost all state govt's are competing with each other to show that they care and hence are restricting admissions in engineering & medical colleges to students with domicile of that state. You can check the rule of your state by visiting webpage of dept dealing with this.

Hello Dinesh,
Of course you can do a certificate course in Canada. But what about jobs afterwards? Most countries are restricting entry to only high skilled jobs & surely skill acquired via certificate course could not be called highly skilled.
But you can spend money and do certificate course.

Generally, you have to possess research qualifications and publications. Please, don't be hasty now. You can think of a job later.