Plesk User Guide
As described in the section Quick Start with Plesk, the first step in establishing your company's web presence is signing up to the services provided by a hosting company (hosting provider). After you subscribe to a hosting plan, a customer account in Plesk is created to enable you to log in to Plesk and use the hosting services and resources like mailboxes, disk space, and bandwidth.
Plesk User Guide
Email User Guide
Setup Of SE Technology emails on various Devices
Email User Guide