Cannot get Katalon to recognise File Explorer when it is opened

Hi, I have a site that I am testing, that during the process flow, has to go off to File Explorer and select a spreadsheet to upload to the page.
I recorded the process and it is fine, until it gets to the file explorer screen. It opens the window, but then does not recognise anything in it. I have tried to create a new object, but it wont let me. Every time I click in the window, Katalon makes a noise and it doesn’t seem to recognise the window at all, so I have no idea on how to get the findTestObject call to work ? I have tried UploadFile, switchWindow to name a few things, but I cannot get it to work !
Has anyone else had this issue and managed to get it to work ?

File Explorer is a native Windows dialog, and Katalon Studio can’t interact with any native Windows dialog. In this case you need an additional third-party tool such as autoIT to help automate actions you need to do on File Explorer

Can you please explain how to use autoIT foor this case

here is my code to find a file in file explorer using autoit:

@Keyword
//### upload file from windows explorer
def uploadFile (TestObject to, String filePath) {
WebUI.click(to)
StringSelection ss = new StringSelection(filePath);

  Toolkit.getDefaultToolkit().getSystemClipboard().setContents(ss, null);

  Robot robot = new Robot();
  robot.delay(1000)
  Thread.sleep(3000)
  robot.keyPress(KeyEvent.VK_ENTER);
  robot.keyRelease(KeyEvent.VK_ENTER);
  robot.autoDelay;
  robot.keyPress(KeyEvent.VK_CONTROL);
  robot.keyPress(KeyEvent.VK_V);
  robot.keyRelease(KeyEvent.VK_V);
  robot.keyRelease(KeyEvent.VK_CONTROL);
  robot.autoDelay;
  robot.keyPress(KeyEvent.VK_ENTER);
  robot.keyRelease(KeyEvent.VK_ENTER);

}