How was Hawaii formed? What made Hawaii? Why does it have so many volcanoes? Why do geologists and scientists say that if they knew how Hawaii was formed then they would know more details about how Earth was formed?

It was formed and made by a hot spot in the middle of the Pacific Plate. There is the hot spot that when the Pacific Plate passes over it, the heat melts the materials and form volcanoes. Since Hawaii was formed, that became a resource for research about volcanoes and since volcanoes make land, they could find out if there are more hot spots.