One common thing to do in a form is to have a toggle and when that toggle is enabled, show a bunch of additional options.

You can see this all the time in the Settings app, for example when you enable WiFi.

How can you do that?

First create a Form view with a Toggle control:

struct ContentView: View {
    @State private var enabled = false
    
    var body: some View {
        Form {
            Toggle("Enable?", isOn: $enabled)
        }
    }
}

Then add this block after the Toggle view:

if enabled {
    Section {
        Text("This appears only if enabled")
    }
}

like this:

struct ContentView: View {
    @State private var enabled = false
    
    var body: some View {
        Form {
            Toggle("Enable?", isOn: $enabled)
            
            if enabled {
                Section {
                    Text("This appears only if enabled")
                }
            }
        }
    }
}

Now with the toggle disabled, the Text view will not be visible:

But when you enable the toggle, it appears: