How is energy created using geothermal?

Answer 1

As suggested by the name - geothermal energy uses thermal energy from the earth (geo). As you get well below the surface of the earth, the temperatures go up quite a bit. In some cases there are fissures that allow fluids to seep down into the hotter areas beneath the surface where they become very hot and may eventually be ejected back to the surface in the form of geysers or hot springs. Geothermal energy uses the earth as the heat source to heat up liquids for turbines instead of using gas flames or burning coal or nuclear reactions to heat it up.

Geothermal energy can also be used simply to heat things up - you can run hot water from the earth through a radiator instead of getting from a boiler in the basement of a building.

Note that you aren't really "creating" energy - you are just changing the form of the energy.