import SwiftUI

struct Detail: View { let value: Int; var body: some View { Text("Detail: \(value)") } }

struct NavStackBasicDemo: View {
  var body: some View {
    NavigationStack {
      List(1...5, id: \.self) { n in
        NavigationLink("Item \(n)", value: n)
      }
      .navigationDestination(for: Int.self) { n in Detail(value: n) }
      .navigationTitle("Items")
    }
  }
}

                    

import SwiftUI

struct ContentView: View {
  var body: some View { NavStackBasicDemo() }
}

                    

import SwiftUI

@main
struct MyApp: App {
  var body: some Scene { WindowGroup { ContentView() } }
}