Where is zPanel www path, path where one can add .php file or html files to be accessible via IP only (no need domain name) ?

How to upload your own file accessible via IP?

Login server via SSH or SCP
Go to folder /etc/zpanel/panel
Copy default index.php file to index2.php: cp -p index.php index2.php
Now you have index.php and index2.php
Now edit index2.php as you wish and access it via web browser YourServerIP/index2.php

To use mysql, just create database from within zPanel

Here is how to upload files to zpanel server: http://internetlifeforum.com/control-panels/3122-zpanel-how-upload-website-files-what-www-path/