We don't all live in beautiful, picturesque scenic areas. Sometimes you've got no choice but to take that video call in a less than perfect space.
Blurring your background can help add professionalism and keep your personal life personal! To do this in a call, select the audio and video settings screen, then the ellipsis (...) then Blur my background.
If you'd rather use an image instead of blurring, go to the same location, but select Show background effects to see a sidebar with some pleasant background images.