How to add user in phpmyadmin

From https://wiki.phpmyadmin.net/pma/user_management :

To create a new user, click the Add a new user link near the bottom of the Privileges page (you must be a "superuser", e.g., user "root").

(emphasis mine)

phpMyAdmin does not handle user management, rather it passes the username and password on to MySQL. create mysql User.

and If you mean, users controlling their own database, go here.

Select the database on the left, then: