so Sue the territory Samule de Champlain explored is canada?

Yes. But I think you should be more specific in your answer.

He also explored the northeastern coast of the U.S.

Yes, Samuel de Champlain explored and established settlements in what is now known as Canada. He was a French explorer who is often referred to as the "Father of New France." Champlain sailed along the eastern coast of North America and explored various regions, including the St. Lawrence River and the Great Lakes. He played a significant role in establishing French colonies in North America, including Quebec City, which became the capital of New France. Today, those areas are part of present-day Canada.