Filed under: iOS
The biggest obstacle I see in new app developers is that they struggle with the basics.
Before you learn about
NSManagedObject, you need to fully understand
case let, and
So, if you know no Swift at all and don't know a similar programming language, start with Apple's Swift Programming Language book and Swift playgrounds (on the iPad or in Xcode on a Mac). Learn how to write extremely simple functions and then small sets of structs/classes that work together.
In Apple's book, I would say to at least get through these chapters
This is enough to get started. But even the simplest real app is going to have Optional Chaining, Inheritance, and Protocols. If you run into something you haven't seen yet, find the chapter where it is discussed.
Then, once you capable of writing small functions on your own, take a look at simple step-by-step app tutorials.