Can you recommend resources to learn about how the banks and modern financial system work?
Assuming you want to study finance and banking from an economic perspective then common introductory texts are
- Exchange Rates and International Finance from Copeland
- Financial Markets and Institutions from Mishkin
- Money, Banking and Financial Markets from Cecchetti & Schoenholtz
Depending on whether you are interested in macro or micro perspective you will want to build upon the above with
- The microeconomics of banking from Freiax
- Intermediate Financial Theory form Danthine, Jean-Pierre
- International Macroeconomics and Finance: Theory and Empirical Methods by Nelson C. Mark
The above-mentioned three intermediate/graduate books also presuppose some knowledge of econometrics, microeconomics and mathematics so you might want to also first study that before delving into these.