Although Windows like Arm OS have been available for several years, Microsoft has never released ISO images. Updates are done via Windows Update or via some virtual disk image (VHDX) file.
Today, Microsoft has finally released ISO files for Windows 11 on Arm.
Like the Windows 64 x11 ISO files, users can use the new Windows 11 Arm64 ISOs to create virtual machines, perform upgrades to a running copy of Windows, or create bootable media to install Windows on Arm to others computers. Microsoft has only released a multi-edition ISO and you will need to use a product key to unlock the correct version for their computers.
Microsoft also mentions on the download page that it may be necessary to include the drivers from the OEMs for the installation media to boot successfully.
For the latest Windows on Arm devices with a Snapdragon X Series processor, users will be able to use the new ISO to install Windows without additional drivers from the OEMs. Windows will install normally, but will be deprived of its full capabilities until the rest of the drivers are installed. After installation you can use ethernet to connect to Windows Update to download the drivers.
Devices with previous generations of Snapdragon processors (Snapdragon 8cx Gen 3, Gen 2, etc.) should have the OEM drivers in the image. Without the drivers, the device may not start, or if it starts, it may not work properly.
You can download Windows 11 Arm64 ISO from here.