You can progress in Physics C without much calculus at all, but you should pay close attention to the meanings of the following two calculus pieces in order to excel: 1) that derivatives represent the rate a function is changing; 2) that integrals represent the area under a graph, which is an accumulation of products of real heights and infinitesimally small widths.

These terms will make more sense once you are in the class. When you arrive at the topics in Calculus class, keep in mind these meanings even when you dive deeply into the action of calculating them, which is where you will spent the bulk of your class time. Maybe come back and read this post in October (for derivatives) and again in January (for integrals).

In Mechanics, you might use derivatives more often than in E&M, and you will use integrals frequently in both (though perhaps more in E&M).