To adjust user roles in Bigcommerce go to Account Settings › Users
List of permissions here and below
The Store Owner can create / delete users and grant permissions from Account Settings › Users. See Adding / Editing Users for more information about creating and removing users.
A user role is a built-in collection of user permissions specific to a particular job. They help to optimize efficiency and reduce the risk of human error by enabling you to delegate responsibilities and permissions to certain users only.
Sales Staff — permissions generally assigned to the person(s) responsible for the sales and/or marketing of your store
Sales Manager — permissions generally assigned to the staff member(s) responsible for processing orders
System Admin — administrator role with all permissions enabled.
Store Owner — the person financially responsible for the account. Only the Store Owner can install, uninstall, or review apps. Once installed, some apps allow the Store Owner to grant access to use the app to other users besides the Store Owner. There is only one Store Owner per store. See Store Owner User Role and Permissions for more information.
Custom — a user-created combination of any of the Sales Staff, Sales Manager and System Admin permissions. Permissions for custom user roles can be selected one at a time, or another built-in user role may be selected and edited.
This setting allows the store owner to grant individual users access to third-party Single Click Apps, and makes the app available from that user's control panel. This list only shows installed apps which support the Single Click App multi-user capability. If the list is empty, then no multi-user apps are installed.