Now you can make calls through Google Duo via the Google Home Hub and speakers. And no set up is required to do it!
However, it would not be a video call. How to make a call through Duo > Just launch Google Assistant and say ‘Ok Google, make a Duo call’ – it would ask, whom you want to make the call to.
> After you say the name, Google will dial it for you and connect the call.
> You can even hang up the phone just by saying, “Ok Google, hang up.”
> In case you are using the Google Home Hub – use the touch screen to choose whom to call and when to hang up
> Call other devices
Calls can also be made to other devices in your home. But while doing that instead of saying the name of the person, say the device instead.
Google Home Hub was launched in October last year at Google’s Hardware event. It is powered by Google Assistant and acts as a smart speaker while handling several days to day tasks like making a shopping list, calling people, commuting details, reminders and many such things. Apart from that it also recognises different voices to identify different users.
It can be used to access every smart device installed in the home including lights, speakers, thermostats. However, it does not have a camera unlike most of its rivals – which has also been upheld by many as a wise move, as an increasing number of users are now concerned about privacy.

Source: financialexpress.com