database connection

<?php
    include_once 'practice3.php';  //add the path of the file containing database connection code
?>

<!doctype html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <title>Exam Practice 1</title>
</head>
<body>
    Hello World<br>

    <?php
        // database connection check
        if($conn){
            echo "Database connected";
        }
        else{
            echo "Connection Error";
        }
    ?>
</body>
</html>


<!-- put this code into another file -->
<?php
        // database connection code
        $dbServerName="localhost";
        $dbUserName="root";
        $dbPassword= "";
        $dbName="test3";

        $conn=mysqli_connect($dbServerName,$dbUserName,$dbPassword,$dbName);