How to load .iso windows installer via grub2?

Question

linux

There is a windows.iso installer in /home/user/, what should I put in 40_custom to boot from this file? boot partition sda2, Linux partition sda4

Answer 1

As far as I understand, there is no direct way (I may well be wrong, but if there was an uncomplicated way to load the installation iso windows into grub2 - it would be indicated in the help on the topic, kmk)
iso boot in grub2 works for Linux, and then, judging by the help , not for all.
as an option:
put and configure Windows in a virtual machine on a VHD disk, and then boot into real hardware from it, which grub 2 can do for example