[CGI] How to use cgi and php on web pages

[#1]

Can anyone help (and before jelv kicks in, I will deal with PAYH when the time comes, if it does so DONT reply with your usual unhelpful replies).
I have a captcha form using php and I have uploaded it into my CGI space.
I also have a number of html pages on my general webspace.
Considering I am using Notepad++ only and not the usual webediting software, how do I link the correct php files to the html file so that they work correctly?
This is all written in text format. So helpful comments only please.

[#2]

If you have an folder in ccgi containing an 'index.php' file, you can run this with "http://ccgi.username.plus.com/folder_name".
Alternatively your can add an anchor in your normal html files -
<a href="http://ccgi.username.plus.com/folder_name"></a>
If you had an initiating file other than an 'index' file you would have to name this specifically in the URL.
Hope this helps.