The water cycle is what causes rain, rivers, and clouds
When the sun heats up the water, the water gains energy, turns from liquid to gas, and evaporates
Runoff and Infiltration
What happens next, is that the water will evaporate off the ground, or even while it is raining. The water that doesn't evaporate (yet) will either become runoff, and move across the surface of the Earth towards a larger body of water. The other water will go into the Earth as ground water.
As the water vapor rises, it loses gas and condenses together into a liquid. This how clouds are made.
When water condenses further, it turns into rain and goes back to the Earth.
Going back to the beginning, not all water is evaporated from the ocean. Some of it is evaporated off of animals and plants.