Warning: Undefined variable $con in C:\xampp\htdocs\loaddata.php on line 8

Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, string given in C:\xampp\htdocs\loaddata.php:8 Stack trace: #0 C:\xampp\htdocs\loaddata.php(8): mysqli_query('SELECT * FROM `...', NULL) #1 {main} thrown in C:\xampp\htdocs\loaddata.php on line 8