1.You can chat with your family members and friends who are on your contact list using the Google message app. The chat can be through text, call or video. 

2.Tap the message app.

3.Tap start chat and name of the contact you want to chat with from the list.

4.To begin the chat, use the keyboard to type a message. Once you are done typing your message, tap 'Send'.

5.When you finish chatting tap the 'back' icon to go back to your contact list.