Every province is different but if you are moving to Canada, you generally have 2-3 months to exchange your license to a Canadian one. If your country has an exchange agreement with your province, you can exchange it, otherwise you have to take the test.
An international drivers license may help if you are not moving to Canada, just staying a little while. They you may be able to drive on it for a while longer than the 2-3 months. However, contact the drivers license authority in your province to find out.
