I only run it when I know I've changed something. As far as technique, you need to be really thoughtful with your CloudKit schema since you are limited in what can change in production. Go watch the session from this year, Evolve your Core Data schema, for some suggestions and thoughts.

I don't know of a specific tutorial but basically what you want to do is to define a model with these properties that is "Codable" (you can look this up - it will help you move back and forth between instances of the model and the JSON data) and then use URLSession to get data from the network and tell JSONDecoder to use your codable model to decode the data. The model specification and networking code is probably ~20 lines of code total, maybe less. Then you can use it with SwiftUI or in any other way needed.

From these errors, the compiler seems very confused. Probably need to see the call site(s) to give any suggestions.