Need Help From People Who Can Edit Well

[SheerCoid]

I have no idea how to do this but can anyone tell me how to put a moving clip of a mouth onto the mouth of a person in a still image? I have no idea what this technique is called and I have no idea how to do it. I have an example from JacksFilm's Youtuber Impressions video attached. The video editor I use is VideoPad Video editor. https://i.ytimg.com/vi/XcdYdQgq_wE/maxresdefault.jpg

[earlsmoviepicks]

Crazy Talk is a PC app that lets you animate the face to match audio. Funny Movie Maker is an IOS app that can substitute moving mouths on still pics.