The rules about the length one can use thier canadian or international license keep changing.
to be on the safe side you can use your canadian/international license until you get your residency and then it only takes less than an hour to get your qatari license. There will only be an eye test and you need the appropriate documents.
If you need help once you get here you can email me directly and i will try and assist you
I am also a canadian and have been working here since the last 3 years.
[email protected] is my address
good luck!!