Hey everyone, I have 3 seperate SSD's, two 2TB SSD's and a single 1TB SSD that has Windows 11 on it. I'm running Bazzite OS on one of my 2TB SSD's, and I used to have Windows 11 on my primary 2TB SSD but I just wiped it to install CachyOS on it so that I can have 4TB of total SSD storage for games on Linux. My current set up is the 1TB SSD has Windows 11, and the two other seperate 2TB SSD's have Bazzite and CachyOS on their own drives.

My primary OS at the moment is Bazzite, and has been for about 6 months now, but I finally stopped being lazy and copied over everything from my old 2TB Windows install to the new 1TB Windows install and then installed CachyOS on the now free'd up 2TB SSD. But after installing CachyOS on what used to be my primary Windows drive, I no longer have access to booting into Windows. I keep a Windows partition for things that don't work on Linux.

When I go into my motherboards boot options, I'm presented with 3 options. 1. Bazzite (default boot option for me) 2. CachyOS 3. UEFIOS which only lets me boot into CachyOS. My Windows files are still safe and accessible on the 1TB SSD so I know everything is still there, I just don't have a way to boot into it anymore. GRUB gives me the same boot options as the motherboard does, so I'm locked out of my Windows install for now.

How do I regain access to my Windows install? Again, everything is still there, I can access my 1TB SSD through either of my Linux installations and see all the files there I just can't find a way to boot into it.

Any help would be greatly appreciated, thanks!