If you have purchased additional domains either from us or from a different registrar to host on your D9 Hosting account, they will not show on your webspace until you create an add on domain for them. You should create an add on domain in your cPanel for each additional domain you add to your account.
When you create an add on domain, you are creating another folder in your public_html folder. The folder will normally be called the name of your new add on domain.
Your public_html folder is where the files for your primary domain are uploaded to.
You should upload the files for your other domains to the correspondingly named folder that has been created in your public_html folder after creating an add on domain in your cPanel.
If you purchased your new domain name from us, you can view and manage it in your Client Area by clicking on the Domains link. If you purchased your domain name elsewhere, it will not show in your Client Area under Domains. You will need to manage this domain with the registrar that you purchased it from.