Google Chat is a communication software developed by Google, built for teams that provide live messaging and team chat rooms, as well as a group messaging function that allows Google Drive content sharing. This is one of the two applications that will replace Google Hangouts, the other is Google Meet.
Follow below steps and activate Google Chat on your Mobile/browser:
Tap on 3 line icon on top left corner
Scroll down and select “Settings”
Select your account
Select General, If you are Android person, check off “Show the Chat and Rooms Tabs”.
If you are iOS person, toggle “Show the chat and room tab” on.
Click on Ok
You will see below notifications
Below is the window from where we can Chat.