Definitely pay more attention to number of working sets per week. Exercises per week means fuck all.
You can do 1 exercise for chest e.g. Flat BB bench three times a week but that could mean anything from 30 weekly working sets to 3 sets per week. One will beat you into the ground and the other will not even be enough volume to maintain gains.
Google “Renaissance Periodization Training Volume Landmarks for Muscle Growth” and “The Hypertrophy Training Guide Central Hub”
Between them you should be able to answer your question and set yourself up for all kinds of future gains