This can be easy or difficult, depending on the exact position. When this position came up recently, I caromed the cueball off the rack into the break ball. The position was such that it felt like an easy shot. It is worth considering. Then he can break with plenty of force, with a smooth stroke.
Straight pool is excellent practice for all pool games.
For example, you may carom off a cluster into a duck. Here is a break that seems to work pretty well. I have messed up my break angle. I am tempted to hit the break ball with draw left, go to the side rail, and directly into the rack. But, if I can get the cue ball close to the corner pocket with high running english which will curve, this break is a natural.