Warning: mysqli_connect(): (HY000/1045): Access denied for user 'root'@'localhost' (using password: NO) in /var/www/html/connection.php on line 5

Fatal error: Uncaught TypeError: mysqli_error(): Argument #1 ($mysql) must be of type mysqli, bool given in /var/www/html/connection.php:7 Stack trace: #0 /var/www/html/connection.php(7): mysqli_error() #1 /var/www/html/index.php(5): include_once('...') #2 {main} thrown in /var/www/html/connection.php on line 7