Output dynamic "div" for every 1.dimension in Array

We try to build a rudimential forum with PHP and MySQL for a school project. We have created a MySQL table named "comments". We try to fetch everything from the table "comments" into an array with:

$sthtitel = $pdo->prepare("SELECT * FROM comments ORDER BY comment_id ");
$sthtitel->execute();
$result = $sthtitel->fetchAll(); 

Display the Array like;

  <div class="comment-wrapper">
        <div class="comment0">Headline</div>
             <div class="box" id="box1">
              <div class="topic" id="comment1">
               <div class="titel"><?php echo $result[0]['comment_titel'];
                    echo $result[0]['comment'];?> <br></div> 
  </div>
        </div>
               </div> 

That works fine.. But we want to display the div "comment-wrapper" dynamically, that a new comment appears automatically.