Lakes do not flow anywhere; if they did, then they wouldn't be lakes. They'd be rivers.
Assuming that you meant to ask, "Which of the Great Lakes belong to both the U.S. and Canada?" then, all but one of the Great Lakes -- Lake Michigan -- belong to both the U.S. and Canada. Lake Huron, Ontario, Erie and Superior are all divided by an international border between Canada and the U.S. All of Lake Michigan is contained within the U.S.
Lake Superior and Lake Michigan both flow into Lake Huron, which flows into Lake Erie, which flows into Lake Ontario.
A river is not a lake. The Humber River flows south from Canada into Lake Ontario. The Humber River flows from the northern regions of Ontario, Canada down through Toronto, Canada and into the Lake.
The Niagara River flows from Lake Erie to Lake Ontario. The border between Canada and the USA runs through the entire length of the Niagara River. The Niagara River begins in both Canada and the USA. It also ends in both Canada and the USA.
It flows north in to Canada and empties into Lake Winnipeg
The Great Lakes are located in both the US and Canada, in the continent of North America.
Great Bear Lake is located in Canada. Canada is located in North America. So Great Bear Lake is in North America.
In both Canada and USA
The Niagara River flows northerly from Lake Erie to Lake Ontario. It is 35 miles long and the border between the USA (New York State) and Canada (Ontario Province).
lake Huron
Great Bear Lake is the highest and largest lake in Canada. The Great Slave Lake is the second largest lake in Canada and is the fifth largest lake in North America.
Lake Superior is the largest lake in North America. It is between the United States and Canada.
You asked this in the "Canada" section. Therefore you know that lake Huron and lake superior form a part of Canada. Now if you know that Canada is in Northern America, then you have your answer...