在PHP应用程序中包含Bootstrap

I'm learning PHP / HTML / CSS. Today I want use Bootsrap.

I use a basic HTML5 template called index.php In this file I want include a footer like this:

<html>
<head>
    <meta charset="UTF-8">
    <link rel="stylesheet" type="text/css" href="ressources/bootstrap/css/bootstrap.css">
    <link rel="stylesheet" type="text/css" href="ressources/css/style.css">
    <script type='text/javascript' src="ressources/script/jquery.js"></script>
    <script type='text/javascript' src="ressources/bootstrap/js/bootstrap.js"></script>
    <title>Index</title>
</head>
  <body>
    <div id="wrap">
      <p>test</p>
    </div>
    
    <?php include('includes/footer.php'); ?>
    
  </body>
</html>

But I dont see my footer in my page. I just put an "Hello World" in my footer.php

</div>