How to create Help Desk System

Hello everybody! I am building an online store and I need help. I have a user database system on my site.

I want to create a support system with tickets. Like this https://codeshack.io/ticketing-system-php-mysql/ .

I copied this script and upload to local server ( I use XAMPP ). Everything is working, but...
I caot coect this script to my site...

I will be cool if somebody can help.
Here's an example of how this should work :

Client Side :
- The person opens the support page....

How to create Help Desk System