If you want to use the same format that was used in the Derby City high run challenge, rack 14 balls, and put the 15th object ball and the cue ball where you please. (Well, almost. Those two balls can't be within 1 ball of any other ball.) Run as many as you can using standard 14.1 rules (calling all shots). When you miss, start from a fresh rack and break. This will give you a lot of practice at standard break shots, which will be good for your confidence in a real game.
The favorite first break shot at DCC for some players is one that you will not have in a normal game: put the object ball on the center spot and place the cue ball 6 inches away for a 45-degree cut into the side pocket. With a little follow, you are guaranteed to land between the two head balls and a scratch is unlikely.
To answer your specific rule about scoring, you must call each shot (ball and pocket) and if you pocket that ball in that pocket without fouling, you score a point for every ball pocketed on the shot.