Facebook integrated Chat rooms in its messenger just a month ago and now it looks like the chat room will soon be part of WhatsApp too. The latest beta marking build number 2.20.163 of WhatApp has recently updated to come with a Facebook chat room support.
According to the information from WABetaInfo, the latest beta build comes with the option of Room inside the popup menu of the share button.
Clicking on the room tab will direct you to your messenger, prompting you to create a room where you can start a group video chat with up to 50 people. The same tab can be found located at other locations i.e. the calls tab of WhatsApp.
For now, The build is only available to be downloaded by selected beta testers in some selected countries including the USA and Europe, but you can always google and download beta WhatsApp sporting build no 2.20.163 to test this feature in advance.
You can alternatively head over to this link of PlayStore where you can enroll as the whatsapp beta tester