Okay I have got the solution ,
when I encounter these messages then after a minute I shout try to move to some thing like TTY 2 or 3 or 4 with CTRL + ALT + F2/3/4
then after login I executed Hyprland by this command :
Hyprland --i-am-really-stupid
and I was in Hyprland
then I have to just choose snapshot to which I want to rollback from GUI
For those who are not on Hyprland and don’t know how start their respective DEs
after logging in to TTY run this command
sudo snapper-tools list
they will see outputs like this :
╭─ankur@ankur in ~ as 🧙 took 3s
[🔴] × sudo snapper-tools list
354 Tue Mar 19 15:23:25 2024 alsa-oss alsa-plugins cabextract faudio glew1.10 icoextract icoutils lib
355 Wed Mar 20 13:04:10 2024 pacman -Su
356 Wed Mar 20 13:04:27 2024 firedragon floorp grimblast-git hyprcursor hyprland hyprlang jfsutils li
357 Wed Mar 20 13:08:41 2024 pacman -S emacs
358 Wed Mar 20 13:08:45 2024 emacs libotf m17n-db m17n-lib
359 Wed Mar 20 19:20:15 2024 pacman -Su
360 Wed Mar 20 19:20:26 2024 firedragon lib32-libunwind libcap
╭─ankur@ankur in ~ as 🧙 took 74ms
[🔴] ×
now suppose that I want to restore a snapshot in front of which the serial number is written like 359 where there is only one thing done which is pacman -Su
so I need to run
sudo snapper-tools restore 359
And it will restore it
And then just reboot and done !!!
Ahh… Actually I saw that thread and read it but the chat was too unorganized in it, that it became hard for a person like me with poor English skills to understand that 