What role did Canada play in the United Nations and in the Korean War?
Canada's involvement in the United Nations was that they were part of the 50 nation representatives that met in San Fransisco to sign a charter that established the United Nations, from April to June in 1945. Canada strongly supported the UN and the idea of collective security, offering money and support for world peace.
as for the Korean war, Canada's involvement was not as significant as the Americans, though the two countries formed a friendship, almost, which proved useful during battle. Canada was part of the war until a truce from both sides was made in 1953.
hope this helped :)