Turn this code into a Task to run Asynchronously on another thread

Turn this code into a Task to run Asynchronously on another thread

I am starting to toy with Tasks and async await. So that I get a better
handle on how to convert my existing code, I thought I would try to try
changing a current method which is run synchronously:
private bool PutFile(FileStream source, string destRemoteFilename, bool
overwrite)
{
if (string.IsNullOrEmpty(destRemoteFilename)) return false;
string path = Path.GetDirectoryName(destRemoteFilename);
if (path == null) return false;
if (!Directory.Exists(path)) Directory.CreateDirectory(path);
if (overwrite)
{
if (File.Exists(destRemoteFilename)) //delete file if it exists,
because we are going to write a new one
File.Delete(destRemoteFilename);
}
else if (File.Exists(destRemoteFilename)) return false;
using (FileStream dest = File.OpenWrite(destRemoteFilename))
{
source.Seek(0, SeekOrigin.Begin);
source.CopyTo(dest);
}
return true;
}
I have tried to simply change the method to async, and dabbled with
Task<bool> but I'm obviously missing something here as neither of them
seem to work. I have experienced Type System.Threading.Task<bool> is not
awaitable.