What is the user registration flow?

New users can register themselves by supplying just the name, valid email and a password. They are then required to verify their email using the link sent before they could login on the site.

Can the admin create user accounts from the backend?

Yes. You can create user accounts on your end.

What are the user management controls available to the admin?

As the site admin, you have access to complete user management from the admin panel. You can edit details such as billing/shipping address, as well as help with password reset or email verification.