First, let's figure out what is a prone float. Front/ prone float is used in 3 out of 4 Olympic strokes. It's the butterfly, breaststroke, and freestyle.
Floating is the most fundamental skill; learning the proper form is crucial. The ability to float correctly allows the body to stay on the surface.
The wrong floating technique slows your swim down. The good float allows your entire body to stay aligned on the surface. The bad floating technique, in contrast, positions your body lower inside the water.
The higher your body stays in the water, the faster you move from point a to point b.