On the Admin Dashboard, click Chat on the left

Above the messages, click the blue circle with the white plus ( + ) sign.

Here, you can search for recipients to send a group or individual chat.

In an existing chat, you can see the details of the conversation on the top right side of the screen.

Click the icon above across from the names of the chat.

Here you can add and remove members from a chat, and view details and media in the chat.