You can obtain the official multi-edition ISO for x64 devices directly from the Download Windows 11 page.

Download Windows 11 Disk Image (ISO) for x64 devices. This option is for users that want to create a bootable installation media ( Download Windows 11 - Microsoft

To download the file, it is highly recommended to use the official source provided by Microsoft to ensure the file is authentic, secure, and unmodified. Official Download Steps

: Scroll down to the Download Windows 11 Disk Image (ISO) for x64 devices section and select "Windows 11 (multi-edition ISO for x64 devices)" from the dropdown menu.