How do i add someone to an existing whatsapp chat

- How do you add someone to an existing whatsapp chat
- How to add someone to an existing whatsapp chat
- How to add someone to an existing whatsapp group chat
- How do i add a contact to an existing whatsapp chat
- How do i add a person to an existing whatsapp chat
- How to add another account on whatsapp
- How to transfer chat whatsapp from android to iphone