Why is there no president in Canada?
Different political system similar to that of Great Britain. We have a Prime Minister instead of a president. The PM is head of the party that wins the federal election. Usually he has a majority and can do what he wants if his own party agrees with it. This makes life easier for him, in some ways, because he seldom has to fight with the legislative bodies that make the laws. But he also has to show up to work in Parliament where the opposition parties will do their best to make him and the ruling party look stupid and incompetent. The US Pres can avoid this daily humiliation and also blame most of his failures on Congress and the Senate if the other party has a majority there.
Canada is a constitutional monarchy with a parliamentary (i.e., "Westminster") form of government. Unlike a congressional form of government with a president who is both head of state and head of government, Canada's head of state and head of government are two different people. Canada's head of state is the reigning monarch, usually represented in the person of the Governor General, and Canada's head of government is the prime minister.