User permissions are broken down into two levels — platform and group levels.
On a platform level, users are either Admins or Members.
Admins have full access to all Groups, settings and features, and they will always be able to add content to Groups.
Members are basic users who by default will only have viewing permissions, as well as the ability to create groups if the setting is enabled.
To change a user's permission level, click on Settings, then on Members. You can use the dropdown menu to change their role.
On a Group level, users can be either Viewers or Contributors. Viewers can only comment and view content, while contributors are able to add content.
When creating a Group, you can choose which role Users will join the Group as.
If you wish to change a user’s permission level after they have joined the group, click on the menu button in the upper right, then select Members. All that’s left is to use the dropdown menu to change their role.