I was just fucking around with EFI boot stuff recently. Legitimate hell. efibootmgr on linux can give info on the current boot options, and might be able to help? I don't know how the M$ boot works since I don't use Windoze.
Consider switching to only booting 
Yeah it is really weird how sparse the info is on this topic.
Consider switching to only booting
I have a terrible secret. I am a gam*r.
What kind of g*mer? Cuz it's possible to game on Linux nowadays. I've been exclusively gaming on Linux for the last 3 years and it is incredible.
Also I don't think efibootmgr can help if your boot files from Windows are gone from the boot partition.
You want as mentioned in the other thread to extract the EFI folder contents from the windows installer ISO (can be opened with any decent archive manager, 7zip works for instance) and place them in the EFI partition. You may need to do some boot repair commands on Windows or it may just work.
almost as soon as I installed linux I uninstalled windows, so I don't know much but wouldn't it work to just install grub and have it do its thing with os-prober? I have a usb with a system rescue iso so that it can find my linux os, then I boot to it, I get into tty and I reinstall grub
I also accidentally deleted my boot partition once, and deliberately other times because I like poking around in the os, I hope this works for you
Os prober isn't detecting windows. I suspect it's because the windows boot partition is gone but I'm not sure how it detects windows exactly.
in some distros os-prober may be disabled by default (because of security reasons iirc, I don't know why it would be unsecure) or you may need to mount the windows partition begore running os-prober
for example in arch os-prober only checks mounted partitions
you can try mounting your windows partition to /mnt or somewhere else where you have an empty folder before running os-prober
Have you tried a bootrec /fixmbr?
Iirc, when someone (definitely not me) did this, I had to do all that fixmbr stuff and then maybe(idk, was a while ago) reinstall the bootmanager I was using.
Did u run across this thread?
This seemed to work for me (I am in a similar situation) but ultimately failed only because (I believe) I have multiple drives and windows tries to incorrectly install on my nvme despite having an efi prepared on an SSD. Seems to be no way to specify the drive for bcdboot. I'm trying again when I have time off. It seems I may need to pull all unnecessary drives to get it on the right one.
Anyway good luck
Edit: I assume bcdboot defaults to my nvme in my specific case because after I tried restoring the boot partition:
i gave up and I nuked all partitions on my windows ssd.
I attempted a clean windows install on the ssd while Linux (with it's own boot partition) lives on the nvme
It creates a new partition layout on the ssd complete with efi parition
then it poops its pants without installing anything to the boot partition it just created. Windows completely refuses to install now.
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