Fatal error: Call to undefined function get_header()
<p>I am using this code to go to a page.  In my directory 
there is theme folder ch.</p>

<pre><code>&lt;li&gt;
&lt;a href="&lt;?php echo get_stylesheet_directory_uri(); ?&gt;/ch/bn1.php"&gt;
    &lt;img src="&lt;?php echo get_stylesheet_directory_uri(); ?&gt;/img/bn1.png"&gt;
&lt;/a&gt;
&lt;/li&gt;
</code></pre>

<p>But going to page url wp-content/themes/live/ch/bn1.php shows this message</p>

<blockquote>
  <p>Fatal error: Call to undefined function get_header() in C:\wamp\www\blog\wp-content\themes\live stream\ch\bn1.php on line 1</p>
</blockquote>

<p>My theme directory is </p>

<pre><code>www/blog/wp-content/themes/live stream
</code></pre>

<p>My page to go to the directory is </p>

<pre><code>www/blog/wp-content/themes/live stream/ch/bn1.php
</code></pre>