I feel exactly the same! I installed EndeavorOS because I liked the default theme lmao

Where do you get your hard drives? Cheapest 1tb SSD I can get is $65, and the cheapest 1tb nvme drive is $80.

My acer laptop did the exact same thing for unknown reasons. When I switched it back to AHCI Arch (btw) booted again but windows broke and I managed to fix it with a Windows live usb. I think I had to use bcdboot and generate a new bootloader.