The United States is very large in land area. Only China, Canada, and Russia are bigger. It has some of almost everything.
The east coast is on the Atlantic ocean. The west coast is on the Pacific ocean.
The United States is not an island. However, one of the fifty states, the State of Hawaii is a group of islands in the middle of the Pacific, almost 4,000 kilometers from the continental US.
The Great Lakes contain 1/5th of all the freshwater on earth.
The Mississippi River is one of the greatest rivers in the world. Mark Twain said it was the longest, but the Nile is probably longer. He said it had the largest drainage basin, but the Amazon's is probably larger. He said "It seems safe to say that it is also the crookedest river in the world, since in one part of its journey it uses up one thousand three hundred miles to cover the same ground that the crow would fly over in six hundred and seventy-five." I haven't seen anything that contradicts that!.