The laws of physics which apply when you are at rest on the
earth also apply when you are in any reference frame which is
moving at a constant velocity with respect to the earth. For
example, you can toss and catch a ball in a moving bus if the
motion is in a straight line at constant speed.
The motion may have a different appearance as viewed from
a different reference frame, but this can be explained by
including the relative velocity of the reference frame in the
description of the motion.