If the group call is already happening, any other internal user can be added via Participants tab, the Moderator can add users to call instantly and they can also join the call.
If the group call needs any external users, that user can join by using the link which may be accessed as shown in figure. If you want to configure the link with a password, check Password protection and enter the password, then share the link to external user. Users will get a page with a field to enter password, he can enter the password and can join the call after entering the password..
Fig. External link share option
TALK The application is used to chat among members. Users can access the application from the navigation menu panel. Talk is Read more
Chat roomIn a chat room it is possible to conduct audio/video calls and send chats. Users can share attachments using Read more
Chat Notification settingsThe user can set chat notification from talk list. There are options to:Favorite: The particular conversation will appear Read more
Search conversation and contactsEnter the contact name you wish to chat with, and you can start chatting and making calls Read more