Can't find where to add a virtual background when using android app on my Samsung Galaxy Tablet

I can't find where the option to set up a virtual background is when I'm using the Zoom app on my Samsung Galaxy Tablet, which I was hoping to be able to use to teach a class. I know where it is when I use Zoom on my computer desktop app, but the android app for a tablet seems to be very limited. Is there no option to add a background when using the app?

More generally, are there any how-to articles about using this particular app? Everything I find is either for a phone or the desktop app, both of which appear to be very different.

Thanks!