I seem to recall there are were (years ago) many ways to do it. One is to have a driver’s license (Canadian, in your case) and go someplace like the CAA (Canadian Automobile Association – you don’t need to be a member) with a photo of yourself about passport size (I took mine in an automated self-photo machine) and pay them for an IDP, then you can drive anywhere in Europe. No test or learning required, though they can still pull you over for breaking the law of course. But in Italy, the law seemed to me to be “stay wide awake and don’t hurt anyone and it’s ok” – people were driving 100KPH on the highway shoulder, driving on sidewalks behind lines of parked cars, ignoring signals and lanes, etc.
I think another way would be to get an EU or Italian permit.
However when I went to the UK about oh ten years ago, I rented a car and didn’t seem to need an IDP, just a USA driver’s license was enough. I also did that in Sweden a few years before.