Figure that moves your mouth to the voice?

I just saw this at BastiGHG. Here: https://clips.twitch.tv/ExcitedGracefulCattleJKanStyle (right at the beginning, ignore the rest)
Can someone tell me what that means and how it works?

You mean voice actor? Or synchronize?

I mean when i say something, the mouth moves from the figure

You just have to animate the character. Draw several times and place the pictures over the words. That doesn't happen live in is not even well done.

If you mean the little animation figure, it is called "lip sync", so I work with Adobe Animate and it is done like on the video:

In the meantime, there are apps that can do it automatically to some extent (but rarely perfect). Smoothlipsync as B.s.