Microsoft doesn't provide a Windows 11 ARM ISO for download by consumers. Even if you have a "genuine Windows 11 License". Complain to them if you want to "get it over with already".

Even Parallels doesn't download an ISO from Microsoft when they build you a Windows VM. When they "get Windows from Microsoft" they are in reality downloading an Windows 11 ARM 22H2 22621.525 (the "GA" release of Windows 11 22H2) ESD file from Microsoft and converting it to a bootable ISO for you behind the scenes. They just hide it well.

If you have a MSDN or corporate licensing contract it's been reported that there is a Windows 11 ARM ISO there. That doesn't help consumers at all. 

Because of Microsoft's pig-headedness, you're going to have to download the ESD and build the ISO from that. The tool that's available here https://communities.vmware.com/t5/VMware-Fusion-Documents/w11arm-esd2iso-a-script-to-create-Windows-... makes it a lot easier than it used to be (and mimics what Parallels does for you). The only downside is that you have to install 2 open source packages from either Homebrew or MacPorts. But once you've done that, it's under a 10 minute process to get a bootable ISO - not much longer than it would take to download one.

I would hope that when VMware gets its blessing for Windows 11 ARM like Parallels did that the tool noted above will no longer be necessary. Until then if you want to run Windows 11 VMs, this is what you have to do. The good news is that it only needs to be done once.

Don't bother with Windows 10 ARM. It's not supported on Fusion 13, and users have not had good luck getting it to run when they've tried. VMware built their Windows ARM support for Windows 11. The only people that care about Windows 10 ARM are those that are running Surface ARM PCs, and Microsoft is pushing hard for them to upgrade to Windows 11. Windows 11 is an overall better experience than Windows 10 ARM and is the only version that contains their x86_64 translation software which broadens the number of existing PC applications that can run on Windows 11 ARM.

Instructions on using the tool can be found in the README, and in the unofficial Fusion 13 for Apple Silicon Companion guide. https://communities.vmware.com/t5/VMware-Fusion-Documents/The-Unofficial-Fusion-13-for-Apple-Silicon...

Version 14 that I'm looking to get published on 22-March will contain a link to a video that does a very nice job of running through the entire process from ISO creation through VM installation.