hi coffeemilk, i suggest you pick up a book to read about the basics of photography to understand the differences between the the basics of photography.
photography is the painting of light
you want light to hit your film/digital sensor to record it.
Shutter is like a door to open for the film/sensor to expose and record it.
To achieve the effect of "moving" you open the shutter "aka door" long enough so when the people is moving, your film/sensor is recording.
that is how you get the effect you want.
in order to get a sharp background you need more tools to help you like placing your camera into something more stable than your hands. Some use a tripod, go find out what it is. Next some use the camera timer to open "the door" Shutter after you press the button to shoot.