PHP - Apache server config DocumentRoot

Question

Recently on my web server I changed the index.php page to 301 to / for SEO purposes. Now that I'm offline and using XAMPP, the document root is set to http://localhost/xampp/ and trying to login is sending the form to / which is the xampp folder rather than that specific app's folder.

I have many different folders for all the different websites I have and if I was to change all the login forms to post to /, how would I set the documentRoot for each one specifically?

Like: localhost/konoro/ root directory is c:/xampp/htdocs/konoro/ localhost/pav/ root directory is c:/xampp/htdocs/pav/

Thanks so much :) I can imagine this has been asked a million times but I couldn't find anything. Cheers, Dom