Can I embed HTML formatting inside of a <textarea> tag?

Question

If I have a textarea block like so...

.. text area content ...
&         
<script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<ins class="adsbygoogle"
     style="display:block"
     data-ad-client="ca-pub-5408099190056760"
     data-ad-slot="7305827575"
     data-ad-format="auto"
     data-full-width-responsive="true"></ins>
<script>
     (adsbygoogle = window.adsbygoogle || []).push({});
</script>        </div>
      </div>
      
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                <span>(楼主)</span>
            
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                <span>2020-11-27 22:06</span>
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<p>There is a very simple way you can achieve that.</p>
<p><strong>First: Customize the <code><textarea></code> to accept and save special chars to DB</strong></p>
<p><code><textarea contenteditable="true" class="form-control" name="setting[header_code]"><?php echo set_value('setting[header_code]', html_entity_decode($item->header_code)) ?>

Second: extract and echo the saved data from DB

Hope it can help you.
Thanks