Click on the "Send A Message" icon and choose communication. You can send group messages: Tap the + icon on the top right corner of the message screen and use (Un)Select All to select or unselect all friends, or add one by one manually.
You can invite a friend to chat through the Chats screen: tap the “add a friend" icon in the top right corner and choose a supportr. You can also create a group: tap the 3 dots icon on the top right corner of the Chat screen > Invite Friend. You can allow/disable the feature or invite more friends to your chat.