Plesk Obsidian can be installed manually or booked fully automatically as an add-on for our VPS products.
The manual installation under Linux is described in more detail in the following Plesk support article: Installing Plesk under Linux
The manual installation under Windows Server is described in more detail in the following Plesk support article: Installing Plesk under Windows Server
The following editions are available for automatic installation:
If automatic installation is selected, you will find your Plesk license key in the VPS administration interface in the control panel. You can access this under the menu item [Server] --> [Edit] (pencil symbol).
The activation key is displayed under the Plesk heading and can be copied from there.