Now Google allows you to blur your background or replace your background with an image in Android App. This facility is already available in Google Meet desktop version. Now Android App users can change their background images.
Before a video call just go to Google Meet and then select a meeting.
On the bottom right of your self view, click Change Background .
To completely blur your background, click Blur your background .
To slightly blur your background, click Slightly blur your background .
To select a pre-uploaded background, click a background.