To Create the ADDON domain please follow the below steps:
1: Open the Plesk panel with the credentials you have received on your registered email id.
2: Once you logged in you will see the "ADDON Domain" option in your Website&Domain section.

3: Once you click on it you need to choose the ADDON Domain which you want to ADD in your panel.
4: The directory will setup automatically for uploading your files once you done click on OK.

