I don’t have this setup myself, but I believe that what you want should be possible using Fedora’s GRUB 2. You just need to regenerate its configuration now that you have installed Windows.
To prepare:
- Make sure you have backups of all important data. (You always should, of course, not only when changing the boot setup!)
- Are you using Bitlocker on Windows 11? (On a default installation, you probably are.) If so, then first make sure you have your Bitlocker recovery key as you may need this.
- From a terminal in Fedora, run
sudo os-proberand look at the output. This is the tool that GRUB uses to find other OSs on the system. Check that it finds and display the Windowsbootmgfw.efifile from your other drive.
Then in the terminal run sudo grub2-mkconfig -o /boot/grub2/grub.cfg. This should update the GRUB configuration to include Windows as a boot option.
Reboot and choose Fedora’s EFI partition from the boot menu. (Also, change your boot priorities in the UEFI so that Fedora is the default, if it isn’t already.)
You should see the GRUB menu including Windows. If you boot into Windows from here, then it will probably ask for your Bitlocker recovery key first time. On subsequent boots (as long as you consistently boot Windows from GRUB, not from the UEFI menu), the recovery key should not be needed.