replace your existing os with archlinux server

archlinux-convert.sh

#!/bin/bash
# This script is experimental and may damage your system.
# Please backup files before run this script.
set -e -x
umount -lf /boot/efi || true
mkdir -p /work ; cd /work
wget -c https://gitlab.com/tearch-linux/applications-and-tools/archstrap/-/raw/master/archstrap.sh -O /bin/archstrap
chmod +x /bin/archstrap
apt update
apt install busybox-static zstd -y
archstrap /rootfs
sed -i 's/^CheckSpace/#&/g' /rootfs/etc/pacman.conf
mount --bind /dev/ /rootfs/dev
mount --bind /sys/ /rootfs/sys
mount --bind /proc/ /rootfs/proc
mount --bind /run/ /rootfs/run
chroot /rootfs pacman-key --init
chroot /rootfs pacman-key --populate archlinux
chroot /rootfs pacman -S networkmanager linux openssh grub --noconfirm
chroot /rootfs systemctl enable NetworkManager
chroot /rootfs systemctl enable sshd
set +e -x
cp /etc/fstab /rootfs/etc/fstab
grep "^[a-z]*:x:[0-9][0-9][0-9][0-9]:" /etc/passwd >> /rootfs/etc/passwd
grep "^[a-z]*:x:[0-9][0-9][0-9][0-9]:" /etc/passwd | cut -f 1 -d ":" | while read line ; do
    grep "^$line:" /etc/shadow >> /rootfs/etc/shadow
    user=$(echo "$line" | cut -f 1 -d ":")
    chroot /rootfs usermod -aG wheel "$user"
done
sed -i "/^root:.*/d" /rootfs/etc/shadow
grep -e "^root:.*" /etc/shadow >> /rootfs/etc/shadow
sync
busybox mkdir -p /debian
cp $(which busybox) /debian/busybox
for dir in $(ls / | grep -v rootfs| grep -v debian | grep -v dev| grep -v sys| grep -v proc| grep -v run| grep -v tmp| grep -v home) ; do
    /debian/busybox mv /$dir /debian/$dir
    /debian/busybox cp -prf /rootfs/$dir /
done
/debian/busybox cp -prf /debian/boot/grub /boot/grub
grub-mkconfig -o /boot/grub/grub.cfg
sync
reboot -f