Go to Customer app > Search an account > Click View > Members
Click Add new member
Fill in the info:
Name
Portal Access: allows users to log in to the web portal.
Role:
Admin
Member
Email
No portal Access: creates login-less users (users without emails and passwords). The most common use of this feature is for IP Phone users who do not have to log in to the Portal and just require an IP Phone license with a PIN code to use the service properly.
Request the member to check their inbox to verify the email