please help me to "swipe" off my open websites from my desktop.

You’re probably describing the iPad feature known as the App Switcher.

Quit and restart an app on iPad - Apple Support

Web pages can be opened in new windows and you’ll get another copy of Safari shown in the App Switcher if you select that, or web sites can be opened in tabs in one instance of Safari. You can close open tabs opened by clicking on the X at the edge of the tab, unless it’s the last and only open tab in the Safari session.

There's no need to force closed apps, as the iPad will sort that out without any assistance. Or you can close apps using the App Switcher, and swiping the apps to force quit off the display vertically. Your choice.

I’d suggest skimming through the App section of the iPad documentation for details on how this works, if you’ve not already:

Switch between apps on iPad - Apple Support

Press and hold on the link, and select open in a new tab from the pop-up, rather than open in a new window.

As for using the App Switcher, yes, a swipe upward can, should, and will force-quit the selected app.

Hello,

What do you mean by "swipe off"? What do you mean by "desktop"? iPad does not have a desktop like a traditional computer. Can you please elaborate more on your question?

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Are you doing this on the Home Screen? It doesn’t work for me. It closes the app but not the tabs. The way I close other tabs is to press on the tab I’m using and a dialogue box opens to Close Other Tabs.