it seems that the php variable is incompatible with html link
Well, PHP runs server-side. HTML is client-side. So there's no way for client-side code to interpret PHP variables.
You need to enclose server-side code in <?php ?> tags in order for it to execute on the server (like you already do elsewhere). Otherwise the server just treats it as any other HTML and returns it to the browser. Something like this:
<a href="specificmonthlyattreport.php?instructor_id=<?php echo $inst_id; ?>&description=<?php echo $description; ?>"><?php echo $userRow2['description']; ?></a>
As you can see, that gets a bit messy. But you can put the whole thing in one echo statement:
echo "<a href=\"specificmonthlyattreport.php?instructor_id=$inst_id&description=$description\">$userRow2[description]</a>";
Notice how the double-quotes needed to be escaped in that one, but since the whole thing was a double-quoted string the variables contained therein would expand to their values.
There are readability pros and cons either way, so it's up to you how you want to present it.
$descriptionis just plain text, since it's NOT within<?php ... ?>delimiters.