I would like to visit Canada for a long time, as it is a large country and I have time.
I am a French citizen and I could not find a Canadian authoritative source that states the maximum duration of a French tourist stay on Canadian territory. The only source I found is the French Ministry of Foreign Affairs{fr} stating I could stay up to 6 months as a tourist without any specific visa.
While I hope the French Ministry does not provide wrong information, I could not find any information backing this up on Government of Canada website (it still helped me determine I do not need a visa)