Do you mean the first example sends to a second page that stores them, or on the same page you want a text field and a hidden field, where the hidden field is set to the value entered in the text field?
Either way, this can't be done with pure HTML. You'll need to use a server side language like PHP/ASP/ColdFusion/etc. if you're trying to set the values.
PHP would do it like so...
// form page 1
First Name: <input type="text" id="tFName" name="tFName" maxlength="50" />
// form page 2
<input type="hidden" name="tFName" value="<?php $_POST['tFName']"/>
field, then do a submit. I'd have to test this to see if it would work, but that's my first thought on it...
What's the purpose? That may help understand a better way to go too...