Google "C++ tutorial". There are plenty of resources on the net for simply learning C++ by itself. You don't need to do the whole thing, either - the first few lessons in whatever tutorial you read will cover the basics of the language, which is where you are having trouble.
The tutorials mainly deal with "C running on a regular computer" - they will use System.out instead of Serial, and they don't have a setup/loop arrangement. But that isn't important for what you are having trouble with, although you will need a compiler if you want to do the examples. Install XCode if you are on the mac. Any linux distro will already have one. Don't know about windows.
Put the work in, do a tutorial. Any of these will do: