Lifetalk,
textarea has nothing to do with PHP, that's html. But, to answer your question, yes, it's possible to pretty much do anything.
I assume that if you are asking about php, you must have a clue as to how html forms work.
Well, in your html form action, all you must do is give the action the filename.ext of your processing php page, such as action='process.php' (and obviously the method='post' as this is your request).
Give each of your input fields "name attributes"
in our process.php page we will then need to refer to those names, so, let's say you have an input field name='serial_number' (no spaces please)... on your process.php page, you will need to say
<?PHP
$serialNumber = $_POST['serial_number'];
?>
test this out by adding below it
an echo
<?PHP
$serialNumber = $_POST['serial_number'];
echo $serialNumber;
?>
now, I wonder what kind of output box you are looking for. PHP (to my knowledge) does not have like a popup "alert" box like javascript does (unless I am mistaking on that one).
so, if you want submit to give you some sort of jump up on the screen and tell you the information, you are going to have to do a crazy mix of javascript with your php, which can get a tad bit messy, but I won't go into that unless you come back and say that is what you were looking for.
I know that it's hard to describe what you are looking to do (I have the same problem at times), but if you can attempt to be a little bit more clear I am sure someone (maybe even I) can help you.
Sage