System login failure after package installation

Introduction does not work, so brief background here. Coming from long term use of Win 10 & unix FBSD. Given the latter away because of complex upgrading problems & more recently desktop unable to find kde5 backends.

Login problem here, after software install with dependancies, not resolved by either advanced options for kernel 5.15.68 1-Manjarox64 or fallback initramfs.

Can I run a script to get back in by editing boot options (E) or grub command line (C)
If it can be done what would the script look like?

Without knowing what software you installed and what dependencies, i can only guess you ended up in some sort of partial update …
Adding kernel boot parameters will not help if the system got broken. You can run it in runlevel 3 by replacing quiet with 3 and then from TTY, as your user run this command:

sudo pacman-mirrors -f5 && sudo pacman -Syyu

If that does not help, see this:

or try to gather as much information is possible to share it here as described here: