Currently i got dual boot with windows10 and Arch. I decided that ill try KDE on a third os so i decided to make another Arch and since i wasnt feeling like doing the entire Arch installation, i just did this with archinstall:
lsblk
cfdisk /dev/nvme0n1
create partitions: 1G [ efi system ] and the rest [ linux filesystem ]
write
lsblk
mkfs.fat -F32 /dev/nvme0n1p7
mkfs.ext4 /dev/nvme0n1p8
lsblk
mount /dev/nvme0n1p7 /mnt
mkdir /mnt/boot
mount /dev/nvme0n1p8 /mnt/boot
archinstall
That gave me an error and now i cant enter to Grub or my original Arch. Im currently in grub rescue, it gives me error: unknown file system.
Here were all my partitions before i fucked it up: