PHP MYSQL connection basic

<?php
    $username ="root";
    $pass="root";
    $database="dvwa";
    $server="127.0.0.1";
    //login to sql_regcase
    $login = new mysqli($server,$username,$pass,$database);
    //check if it working or not
    if ($login-> connect_error){
        die("connection failed: ". $login->connect_error);
    }
    //echo "woohoo..!! connection is successfull<br>";

$sql = "SElect user_id, first_name FROM users";
$result = $login-> query($sql);

if ($result-> num_rows > 0){
    //print data of each row
    while($row = $result -> fetch_assoc()){
        echo "<b>id: </b>". $row["user_id"]. " <i>Name: </i>".$row["first_name"]."<br>";
    }
} else {
    echo "nope, nothing found";
}
$login->close();

?>