How do I display PHP file contents on front end of WordPress?

Apparently single quotes are a thing in this scenario, this now returns the results.php file contents:

<?php
echo include('skiddle-php-sdk-master/demo/result.php');
?>

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)