On openSUSE with the default partitioning and Snapper you rollback this way:
- Boot to the snapshot from the grub menu.
- Test to make sure it's working.
- Run
sudo snapper rollback
and reboot.
It may differ for Arch depending on how you have it set up. If you don't have grub entries for the snapshots, you could install and configure grub-btrfs. It's easy, but there could be gotchas depending on how you are set up currently. Maybe give this a read and see if it's helpful: https://www.lorenzobettini.it/2023/03/snapper-and-grub-btrfs-in-arch-linux/
(Not my blog, it just looked useful)