I tried writing a .img file to an existing partition (the partition that my computer boots into). When I rebooted my computer it booted to "GRUB Rescue" and said "Unknown filesystem". I tried changing the BIOS and plugging in a USB but it didn't work.
This is my main computer and I really need help. I screwed up big time.
insmod normal
I got this error:error: symbol `grub_file_filters_all' not found.
. – re2VjqTVJwsgq-NZufnN4e56W1RAHL Oct 15 '20 at 17:35insmod normal
didn't solve the problem of user53817 who asked the linked question either, but Boot-Repair did solve the problem as mentioned in UPDATE 5 at the end of the question. – karel Oct 15 '20 at 19:23