Congratulations on your purchase!
A motorhome is largely a big collection of things that aren't all that much related to each other. In other words, most of the systems are more or less independent. This means you can figure things out one at a time to a large extent. (That's not to say that everything is independent, but you don't need to understand the water heater to extend the awning, and vice-versa.)
The Beginning RVing forum here has a bunch of helpful sticky subjects that you might find useful to read through. Cruise America has a
pretty good orientation video on their rental RVs, much of which is generally applicable to class C's (and it should be fairly obvious when things don't apply to your own RV).