config.php

<?php

$host="localhost";
$db_name="local1";
$db_user="admin";
$db_password="pass";

$con = mysqli_connect($host, $db_user, $db_password);
$username = $_POST["username"];
$password = $_POST["password"];
mysqli_select_db($con, $db_name);
$query = "SELECT * FROM users WHERE username='$username'";
$result = mysqli_query($con, $query);


  echo "<pre>";

  if (mysqli_errno($con) !== 0) {
    echo "SQL error: ", htmlspecialchars(mysqli_error($con)), "\n";

  }
  echo "</pre>";

if (!$result) {

    exit();
}
$logged_in = false;
    $row=mysqli_fetch_array($result);
  if ($row["password"] === $password) {
    $logged_in = true;
    echo "<h1>Logged in!</h1>";
    echo "<pre>User level: ", $row["user_level"],  "</pre>";
    if ($row["user_level"] >= 50) {
      echo "<p>Congarts :D ! you have found a high level user \n tell the admin to always use intval(GET['id'])</p>";
    } else {
      echo "<p>you didn't find a user that has a high level.</p>";
    }
  }
  else
    echo "Wrong Username or Password :( !";