If you just need the ISO file without a USB drive, use Rufus, let it download, click to save the ISO, then cancel the USB writing process (or close Rufus after saving).

Rufus Download Windows 11 Iso · Essential & Trusted

If you just need the ISO file without a USB drive, use Rufus, let it download, click to save the ISO, then cancel the USB writing process (or close Rufus after saving).