How to make a video with a background?

How to make a video with a background?

I have a friend who has a new galaxy and asked me how can you make a video with a background of let's say Tahiti or the space station?

So basically they want to take a picture from the internet and have that as a green screen as they make a live video of themselves

Can new phones do this on their own? Or is there a free app?

Tia

I don't know how to do that with a phone but Zoom has it as a built-in option.

There appear to be a number of YouTube videos showing how to use one's background of choice.

https://www.google.com/search?q=How+to+make+a+video+on+my+phone+with+a+background%3F&oq=

Interesting looks complicated. Too bad nothing in galaxy software

I believe the video above is doing something more complicated than just a basic changing of the video background to a downloaded picture of Tahiti, which is actually probably simple to do. Installing the free app, or similar, and trying it out would seem to be harmless. Some Samsung higher end phones do have built in video editors, I believe.