SwiftUI Trun String to sendable CSV

Question

My current code is able to show the ActivityView, but does not show Airdrop, but that is not the main problem, i apologise for that, but i can't really fix the one, without fixing the other ...

func genCSV() -> String {
    return "field1, field2"
}

struct ActivityViewController: UIViewControllerRepresentable {

    var activityItems: [Any]
    var applicationActivities: [UIActivity]? = nil

    func makeUIViewController(context: UIViewControllerRepresentableContext<ActivityViewController>) -> UIActivityViewController {
        let controller = UIActivityViewController(activityItems: activityItems, applicationActivities: applicationActivities)
        return controller
    }

    func updateUIViewController(_ uiViewController: UIActivityViewController, context: UIViewControllerRepresentableContext<ActivityViewController>) {}
}

Suppose the genCSV() fund actually returns valid CSV-Strings, how do I use it, to combine it with the ActivityViewController to send the generated CSV-File(obviously I still need to generate the file, that is my main problem right now)?

var body: some View {
        NavigationView {
            VStack {
                HStack {
                    Button(action: { //action that triggers the sheet }) {
                        Image(systemName: "square.and.arrow.up")
                            .resizable()
                            .scaledToFit()
                            .padding(.all, 50)
                            .frame(width: 150, height: 150)
                            .background(Color.gray.brightness(0.18).opacity(0.5))
                            .clipShape(Circle())
                    }
                    .sheet(isPresented: self.$viewModel.airdropVisible) {
                        ActivityViewController(activityItems: [URL(string: "www.apple.com")!])
                    }
                }
            }
        }
    }

This is my current ContentView. Any helps or pointers are appreciated, I searched through a lot of Google results, and did not really find a good answer.

One Issue remaining also is, that Airdrop does not even show up in the ActivityViewController.