First off calm down,
Secondly I don't understand your concern! If you are already in Canada, and you have your residential address in Canada they will conduct an interview here (if any needed, rarely in regards to CEC applicants).
If you are in your home country and you have your address in Canada, then you have to change your residential address ASAP so they can arrange the interview in your home country!
If you are in your home country and you have your address in your home country then they will take care of the interview in your home country.
All in a nutshell, they will arrange the interview depending on your residential address.
Thanks for the reply..My address in the interview letter is Canada,but still they r asked no me to go to home country...
Best of luck mate,