Use shelly instead of pacman

SecureBoot.sh

@@ -1,3 +1,13 @@
+#!/usr/bin/bash
+
+# Detect fish shell and ask user to switch to bash (bash-only syntax)
+if [ -n "${FISH_VERSION:-}" ] || case "$SHELL" in *fish*) ;; *) false ;; esac; then
+  echo "Warning: fish shell detected."
+  echo "This script is written for bash and may have syntax issues under fish."
+  echo "Please switch to bash first and re-run it, e.g.: bash $0"
+  read -r -p "Press Enter to continue anyway, or Ctrl+C to cancel..." </dev/tty || true
+fi
+
 # Install Prerequisites
 sudo pacman -S --needed -noconfirm efibootmgr sbsigntools mokutil sbctl grub