The following code snippet seems to be working fine to launch the saved file, in Andriod 9 version.
Context context = Android.App.Application.Context;
if (file.Exists())
{
Android.Net.Uri path = Android.Net.Uri.FromFile(file);
string extension = Android.Webkit.MimeTypeMap.GetFileExtensionFromUrl(Android.Net.Uri.FromFile(file).ToString());
string mimeType = Android.Webkit.MimeTypeMap.Singleton.GetMimeTypeFromExtension(extension);
Intent intent = new Intent(Intent.ActionOpenDocument);
intent.SetDataAndType(path, mimeType);
context.StartActivity(Intent.CreateChooser(intent, "Choose App"));
}
But this code throws errors in Android 11 - API 30 and does not launch the file.

