Permissions on digital outlets, like other things, are managed through Profiles: each profile has certain permissions with respect to the sources they can access, the actions they're allowed to perform on the platform, and the destinations where they can publish.
For each digital outlet that you want to publish to, the first step is to set up a "Destination" which links your Wildmoka account to the digital destination, like Facebook or Twitter (but this also applies to FTP servers, custom destinations, RTMP streams, etc). Next, give access to one or more profiles (in User Management) to have permissions to publish to that destination. Finally, assign that Profile to any number of users so they can share to those destinations as set up in the Profile.