Once you have added the domain name in the Addon Domains section inside your cpanel. A directory will automatically be created inside of your /public_html directory.
Ex. The Addon domain is test123.com.
When you add it, it will show up as /public_html/test123. Everything should now be uploaded inside this directory for that addon domain name that was created.
Note: In order for this to function correctly and for the site to be viewed, the DNS must match as the primary domain names DNS.
