this code works with php but how to use it for wordpress?
Hope you can help me! iam currently learing to build a wordpress site from the scratch. But this is not working for some reason

<?php
/*
  Template Name: inlog
*/
  ?>
  <!-- Form -->
  <!-- After the user fills in the form, the application wil check if it already exists -->
  <!-- If it already exitsts the user will get the option to get directed to the result page -->
  <!-- Else the user will get directed to the band form -->
  <form method="POST" class="main_form" action="">
    <div class="main_form_input">
      <input type="text" name="name" required placeholder="Username">
      <input type="text" name="email" required placeholder="Email">
    </div>
      <input type="submit" name="Submit" value="Log In">
  </form>
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST'){
    mysql_connect('localhost', 'root', '');
    mysql_select_db('td-game.com');
// Get values from form 
$name=$_POST['name'];
$email=$_POST['email'];
// Insert data into mysql 
$sql="INSERT INTO klant(naam, email, date) VALUES ('$name', '$email', Now())";
$result=mysql_query($sql);
 header("Location: ./pages/voting_page.php");
}?>

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