Getting started with PHP File-Trying to Create a Guest Book for My #IndieWeb Blog

I have very limited experience with PHP. Basically I have copy and pasted contact forms for years and occasionally hack around in WordPress.

More recently I have started to dig into Known as I find stuff I would like to do on my site.

Right now I am trying to have a php form on a website and spit out the results on the same page. I don't want to save the data anywhere but the webpage.

Here is my attempt to write the form and the template. Would love feedback on the fundementals. Here is a link to a Gist as well.

If I can get this part proper I can then go and figure out what magic I need to do to make it happen.

<main>
     <div class="contain">

  <div class="Contactwrapper">
    

    <div class="form">
      <h3>Send us a message</h3>
      <form action="guestbook.php" method="POST">
        <p>
          <label for="name">Your name</label>
          <input type="text">
        </p>
        <p>
          <label for="website">My URL is...</label>
          <input type="text">
        </p>
       
        <p>
          <label for="instagram">Instagram</label>
          <input type="text">
        </p>
        <p>
          <label for="twitter">Twitter</label>
          <input type="text">
        </p>
        <p>
          <label for="email">Email Address</label>
          <input type="text">
        </p>
        <p>
          <label for="subject">Topic</label>
          <input type="text">
        </p>
        <p class="full-width">
          <label for="text">Write your message</label>
          <textarea name="" id="" cols="30" rows="7"></textarea>
        </p>
        <p class="full-width">
          <button>Send</button>
        </p>
      </form>
    </div>
  </div>
</div>
    <section class="h-feed">
            <h2 class="p-name">My Guestbook</h2>
            <h3>Curated by <span class="p-author">Insert Name</span></h3>
     <ul class="h-entry">
  <ul class="h-card">
  <li class="p-name">
            <?php echo htmlspecialchars($_POST['name']); ?></li>
   <li class="u-url"><a href="https://<?php echo htmlspecialchars($_POST['wesbite']); ?>"><?php echo htmlspecialchars($_POST['website']);</a></li>
  <li><a href="https://instagram/<?php echo htmlspecialchars($_POST['intagram']);"></a></li>, 
<li><a href="https://twitter/<?php echo htmlspecialchars($_POST['twitter']);"></a></li>, 
 </ul>
   <li class="dt-published">    <?php $currentDateTime = date('Y-m-d H:i:s'); echo $currentDateTime;?></li>
   <li class="p-content"><?php echo htmlspecialchars($_POST['name']); ?></li>
   </ul>
    </section>
    </main>