Data models using structs (value types in general) - How to keep everything in sync? - swift

Question

I hope this question is not too generalized or broad. But I've been trying to grasp this concept for the past week and I don't make any progress. I've read dozens of articles and answers on StackOverflow but nobody seems to address this properly. Everyone is always using the most basic models that don't intertwine at all (see example). It might just be me being stupid.
I'm really struggling with understanding how a good data model works and how to implement it into an app. I want a method that is consistent and convenient throughout the app. I have an example.
Let's say I want to create a data model like this:
struct Person {
var name: String
}
struct Car {
var name: String
var owner: Person // Link to a car struct
}
struct Garage {
cars: [Car] // Array of car structs. Usage: Maybe a list view that shows all cars
}
This covers some of my big problems using structs as data models:
References between models - Structs are value types, referencing another model simply creates a copy of that model. Thus, I end up with multiple copies of the same data. What if that data changes? Or what if the reference itself changes (i.e. the owner of a car)? Observing a Car struct using, for instance, Apple's Combine framework doesn't really work because of this owner reference and the fact that it just is a copy of the original Person.
Arrays of models - This seems to be even more tricky. I have to decide whether I want to use the array as a whole (i.e. for a list view) or if I need to use individual elements (i.e. passing a car to a detail view). When trying to keep everything synced it seems like I have to choose one of the two. Doing both at the same time looks impossible. I could create two separate models, each for its own use case but again, I end up having multiple copies of the same data. It just doesn't work.
(To make it more clear: What I mean is I always have to decide between Observe([cars]) and [Observe(car)]. Doing both doesn't seem to work.)
How would I use this data model inside a project with multiple views like a "CarListView", "CarDetailView", "PersonDetailView", etc. without ending up with dozens different copies of my data that are all different?
I really want to use structs because the code becomes so simple and beautiful. But it just seems to be really annoying and partially impossible. However, wherever I go people advice using structs over classes in most cases. The example looks like a fairly basic and normal use case. Is it not suitable for struct usage? Am I just stupid?
I'd be extremely grateful for any insight on this topic. This is driving me crazy.