In general, a computer program is similar to a cooking recipe. It's a set of detailed steps designed to accomplish a task. In computer science, we don't often call something a recipe, rather we call it an algorithm - but it has the same basic meaning as a recipe.
In most cases, you know exactly what you want the computer to do. Our problem then becomes ''How do I tell the computer to do what I want it to do?''. I usually start solving this problem by writing down in English (in the form of a recipe, for example) what I want to tell the computer to do. Then I'll rewrite that in simpler terms that are very explicit and concise - I call this ''pseudo code''. I then take my pseudo code and write it in actual C++ code. Well, I lied. I used to do this when I first started programming, but I don't anymore unless I'm working on a very complex program. But until you get some experience under your belt, I recommend using the above strategy unless you feel very confident that you can do without it.
So, at the moment, you have the basic tools of C++. You can put these tools together in various ways to make a variety of different programs. In fact, you may now have enough information to do the first problem in the homework assignment that Dr. Glinert will be assigning some time soon.