I think you need to pick up an economics book. Try this one.
Principles of Economics by Mankiw is what you are looking for.
I started with vulgarisation but it didn't lead me very far. This is a reference textbook used by economics students around the world. It's surprisingly entertaining and teaches you the basic concepts of macro and micro economics.
We read Greg Mankiw's Principles of Economics . It's the Harvard undergraduate text--orthodox as they come.
Saying barter plays a limited role in virtually all economies, modern and historic, is different from saying it was money's progenitor, as Adam Smith wrongly speculated. The former is true. The latter is not.
TL; DR Money and banking isn't always taught in introductory economics. The "bartering noble savage" myth is not something economists cling to.