In SwfitUI it is extremely easy to add a sheet layer on top of your current view. You just need to append the .sheet(...) modifier to your view:

ZStack {
  Text("My main view goes here")
}.sheet(isPresented: $shouldShowSheet) {
  Text("My sheet content")
}

The sheet modifier accepts a boolean value as a binding and the content that should be displayed when the boolean value is true.

If within the sheet view you want to programatically dismiss the sheet you can use the dismiss environment function provided:

struct CreateProjectView: View {
  @Environment(\.dismiss) var dismiss

  var body: some View {
    HStack {
      Text("My sheet")
            Button(action: {dismiss()}) {
                Text("Dismiss sheet")
            }
    }
  }
}