Thank you so much for your responses @RedFox1 and @roosterboy !
Fireship’s video and the PostgreSQL article were super informative.
Although I am extremely confused and have so many questions… Forgive me, CWC iOS Foundations and Databases were my first serious coding experience.
I haven’t found any FaunaDB tutorial for an iOS app so I guess I’ll need to figure out the implementation on my own. I have a feeling that setting up a serverless database for my app like I did with Firebase is going to take a hella lot more brainpower for a SQL database…
What is a framework? What does it mean that Apple uses SQLite as its framework for CoreData? (I think I remember hearing that CoreData uses SQL “under the hood” but I didn’t really get what it meant) What is GraphQL and why do I need it “on top of” my database? Why SQLite over PostgreSQL (or vice versa)? What is a schema?
I googled all these things and ended up even more confused, so I know those questions are way too complex to be simply answered on a forum.
Bottom line, it seems that I must first wrap my head around all that foundational stuff. So in the mean time I subscribed to Codecademy Pro for the back-end engineer path and started studying. I can’t stand feeling clueless 
How did you first learn all this? I’d be extremely thankful for any advice you can give me 