The movement drills are for practicing head movement and body shitfting to help move in and out of striking range as safely as possible. Parries and covers are to be as small as possible to redirect or deflect then get right back to striking or control position. We start practicing in the air then mitts, bags, and partners. the basic combo is: Jab, cross, hook,overhand, uppercut then adding a kick on the opposite side.
People that practice standing still in front of the bag get a little too good at standing still usually, so this is just getting them used to moving and stiking simultaneously.
All the best,