To create an email account for your domain in Plesk, log in to Plesk.
After that, switch to the email section on the left side.
There you have the option to create a new email address.
Email account options
If you only want one email address for sending/receiving emails, "General" is the relevant section for you.
Email address
The first thing you do is select the email addresses you want.
You can allow access through this account in Plesk. If this is not desired, uncheck the box here.
External email address
Here you can specify an email to reset the password, but this field can be left blank. You can reset the password at any time via the Plesk interface.
Password
Now you can set a password for the mailbox. This must be confirmed one more time.
You can also reset the password at any time via the Plesk interface.
Mailbox
If you want to limit how big the mailbox should be, you can specify a value here in KB, MB, GB or TB.
The "Unlimited" option is the default here. This means that there is no limit to the size of the mailbox.
Description in Plesk
Here you can still create a note for the mailbox.
Then confirm the entry with "OK" and the mailbox will be created.
If you want to create a forwarding to other mailboxes, you can find instructions for it here.