I\'m sort of experienced with PHP and MySQL so I kind of get the hang of things, however I\'m sort of trying to get something that may be over my level (not really sure the diff
You'll need to use JavaScript to do it. Send an AJAX request to a page in the server which will fetch the details of a user for you, then return the results to JavaScript.
Once you have the data in your JavaScript, use DOM manipulation to populate the second with the results.