Certificate

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.

Hi,
The stay back time is equal to the course duration.

Hi Nimmakalaya,
This depends from university to university and also if your distance B.Tech is recognised by UGC or not. Please email universities in USA admits enquiring.They will get back to you. You can also share a soft copy of your degree with them.

I would rather suggest you to do SAP FICO for better future. Main reason is that most of the big companies uses SAP as an accounting software.

Yes, a commerce student can surely do this course.