Please locate the root folder of your theme. It is usually in /wp-content/themes/THEMENAME and edit single post template file. In most cases it is single.php file, but it may differ depending on theme.
Add the following code inside the main loop:
echo do_shortcode('[wise-chat mode="0" channel="Post #'.$post->ID.' channel"]');
This will open “Post #ID channel” channel as the classic chat.