Voice messaging, voice calls, video calls and so on has been the main features of WhatsApp, but video messaging is slow to come online.
Recently, Meta announced that WhatsApp can record and share short personal videos (i.e., video messages) directly in chat. Video messages are a way to reply to chats in real-time, up to 60 seconds each, and are protected by WhatsApp’s end-to-end encryption.

Source Meta official website
It is learned from the official website, WhatsApp send video messages just like sending voice messages, users just need to click to switch to video mode, and press and hold to record video, you can also slide up to lock and hands-free recording video. When a video is turned on in a chat, the video will automatically play on mute and tapping on it will activate the sound.
Officially, video messaging has started rolling out and will be available to everyone in the coming weeks.