In one point perspective drawing does the front plane that is facing us ever change shape or get smaller if you draw a box?
If I keep drawing boxes that is below the horizon line lower and lower in 1 point perspective, will the front face get smaller or disappear eventually?
Depends on your projection. For the classical front plane is a flat plane perspective, no it never goes away. The plane is always as big no matter how far in the view angle you move it. This is after all a ideal camera your modeling.
But some real world cameras actually do not all have a plane shaped focal zones, they are actually spherical in that case yes it does scale down and eventually disappear. Some rendering engines can specify what kind of hider flat pr spherical. By tracing it can be arbitrarily complex also.