I get an error in php like this :

Warning: mysqli_connect(): (HY000/1045): Access denied for user 'mrjgames_com'@'10.27.17.13' (using password: YES) in /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/config.php on line 4 Connexion impossible ! Access denied for user 'mrjgames_com'@'10.27.17.13' (using password: YES) Warning: mysqli_query() expects parameter 1 to be mysqli, bool given in /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/config.php on line 12 Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, null given in /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/config.php on line 12 Fatal error: Uncaught Error: Call to a member function query() on bool in /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/config.php:24 Stack trace: #0 /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/index.php(2): include_once() #1 {main} thrown in /customers/1/0/3/mrjgames.com/httpd.www/scores/scores/config.php on line 24

Is this example outdated!?

Which PHP version should I use 7.1 or 7.2 or 7.3?