Why do Americans get tornadoes and hurricanes but not Canada?

Canada does get tornadoes and, in a few cases, hurricanes. It just gets fewer than the United States.

Some notable Canadian tornadoes include the Edmonton, Alberta tornado of July 31, 1987 and the Elie, Manitoba tornado of June 22, 2007.

Notable hurricanes in Canada include Hurricane Gustav of 2002 and Hurricane Juan of 2003

Canada is colder on average than the United States, tornadoes form best in hot weather.

Hurricanes form over tropical water and usually do not stray far from them. Most hurricanes weaken to below hurricane strength before making it very far north but occasionally do reach Canada.