You can remove a domain in Plesk by following this tutorial.
1. Log in to your Plesk account.
2. Click on Websites & Domains from the Sidebar Menu.
3. Under the list of domains, click on the More icon 
in front of the domain and select Remove website.
4. Confirm with Yes to remove the domain.
1. Log in to your Plesk account. 2. Click on Websites & Domains from...
1. Log in to your Plesk account. 2. Click on Websites & Domains...
1. Log in to your Plesk account. 2. Click on Websites & Domains...
A subdomain is an additional part of your primary domain. Please, follow this...
Follow this tutorial to add a new domain to your Plesk account. 1. Log...
