You can enable the service after its purchase here.
When purchasing the service, your order wizard should specify the domain name for which an antivirus scan will be run.
Please make sure that hosting for your domain is functioning. Hosting can be provided by any hosting provider.
After service activation, you should go to the service control panel from your personal account: the Services section -> Licenses and then click the Control Panel button from the list of services — it will open in a new browser tab.
Then you need to sync the website data with the antivirus service. Download a synchronization file from the control panel or specify access to the website via FTP.
After placing the file (or specifying FTP access), the website will be synced with the antivirus service automatically.