This is my code. Could you correct? Thanks in advance
Code:
<?php
echo <<<_END
<DOCTYPE html><html><head><meta charset="utf-8"></head>
_END;

require_once'login.php';
$connection=new mysqli($db_hostname, $db_username, $db_password, $db_database);

if($connection->connect_error) die($connection->connect_error);

if (
...