How to add plain text code in a webpage?

Look at how this website itself achieves this:

<p>For example, if I have <code>&lt;p&gt;&lt;div&gt;&lt;/div&gt;&lt;/p&gt;</code>, I want the div to display in the browser as text not have the browser interpret it as html. Is this complicated to do?</p>

You need to replace the < and > with their HTML character entities.

There are many ways to use:

1. Replace < with <

   `<h1>This is heading </small></h1>`
   

2. Place the code inside </xmp><xmp> tags

   <xmp>
       <ul>
           <li>Coffee</li>
           <li>Tea</li>
       </ul>
   </xmp>
   

I do not recommend other ways because they do not work on all browsers like <plaintext> or <listing>.