How to add a new essbase user and grant priviledges

Hi, I'm wondering how to add a new essbase uesr and grant priviledges to it.

Essbase version 11.1.2

Essbase was installed automatically together with BIEE version 11.1.1.7 when I installed the BIEE.

And I installed Essbase Administration Services client on my laptop to manage the Essbase.

I logged in the EAS using "biadmin" user that was created when I installed BIEE.
 *This "biadmin" user is commonly used among components ( Weblogic, Fusion Middleware, BIEE consoles etc.).

I can confirm that there is "biadmin" user on the left pane of EAS.
 *Managemnet Server - User - biadmin

I tried to add a new user and right clicked on the "Management Server - User" tree,