So probably you have seen my previous thread... big whoop, but no help... the init=/bin/bash doesn't work, so how do i reset it using the debug shell? Instructions are rather unclear -> 1. Append systemd.debug_shell to the kernel parameters.
2. This will do a normal boot but start debug-shell.service which runs a root shell (/bin/sh) on tty9. Press Ctrl+Alt+F9 to access it.
3. Use the passwd command to create a new password for the root user.
4. When done, stop debug-shell.service.
I think this is the only thing that could be unclear. At the GRUB boot menu, press e to edit the boot line, append the text to the boot line (the one with quiet at the end of it), then press F10 to boot.
However, looking at your other thread and your nearly-two-year-old Garuda installation, you should reinstall. Many things have changed in Garuda and a fresh set of software and defaults will work a lot better than the old installation, even once updated.