grub-reboot Windows

Not really an opensuse only question, but…
Is there a way to control/easily edit grub2 files to grub-reboot from Win10 (headless).
ie Rebooting from Ubuntu to Win10, with Ubuntu being default, but also have opensuse on the machine, so may want to boot from Win10 to the non-default OS.
Thanks.

Hi
In windows use bcdedit AFAIK.