The basics of this are taking input from a Web form and putting it into a text template and then displaying the output. This is pretty much standard fare for Perl CGI.

The reason the script calls itself is so that the program that produces the form is also the program that processes the responses. It's efficient and perfectly valid. What the CGI does is check for the form submissions, and if they aren't there, it shows you the form. If they are there, it shows you the result.

All the code you need is there on the page you sent me under Files. Maybe you are having trouble setting it up?

In the example file, they are using HTML comments to position the words. You won't be able to see them if you're trying to view the file in your Web browser and it is showing up as HTML. Use Notepad or an equivalent instead.