# cat /etc/grub2.cfg | awk -F\' /^menuentry/{print\$2}
Red Hat Enterprise Linux Server 7.9 (Maipo) <<< Entry 0
Red Hat Enterprise Linux Server 7.9 (Maipo) <<< Entry 1
Red Hat Enterprise Linux Server 7.9 (Maipo) <<< Entry 2
Red Hat Enterprise Linux Server (0-rescue- 7.9 (Maipo) <<< Entry 3
# grub2-set-default 2
# cat /boot/grub2/grubenv | grep ^saved_entry
saved_entry=2