cant connect to sql

[the-air-cyborg]

Warning: mysqli::__construct(): php_network_getaddresses: getaddrinfo for host failed: No such host is known. in C:\xampp\htdocs\School-Management-System---PHP-MySQL-master\database.php on line 8

Fatal error: Uncaught mysqli_sql_exception: php_network_getaddresses: getaddrinfo for host failed: No such host is known. in C:\xampp\htdocs\School-Management-System---PHP-MySQL-master\database.php:8 Stack trace: #0 C:\xampp\htdocs\School-Management-System---PHP-MySQL-master\database.php(8): mysqli->__construct('host', 'schoolnew', Object(SensitiveParameterValue), 'schoolnew') #1 C:\xampp\htdocs\School-Management-System---PHP-MySQL-master\index.php(4): include_once('C:\xampp\htdocs...') #2 {main} thrown in C:\xampp\htdocs\School-Management-System---PHP-MySQL-master\database.php on line 8

do you know whats the problem here?