If you want to message the same content to two people then the broadcast message option is a good choice. It is the list of two or more people from your Viber contacts.
You can send them the same message without adding them in group chats. You have to create the list for broadcast. In this way, you can write one message and send it to multiple people on different chat windows.
You can add or remove the contacts from the list. Moreover, you can rename the list as well.