If something is over it is finished, across, or above. When a movie is over, you get up and leave. A blanket that's over your feet covers your toes. A painting over a fireplace hangs above it.
Over is related to the German word über, meaning "above," like putting one piece of paper over another, or a ruling over your school, you popular person. Over can describe a distant position: your phone is over there. Or it can mean "throughout an area," like traveling over roads and oceans, or going over the plan before the team starts working.