Two issues with KDE that might make it look worse than it actually is on a first glance

So, after I installed Xfce following this https://linoxide.com/install-xfce-desktop-on-arch-linux/ (basically using the commands that are listed in the website and selecting Xfce before logging in) I was unable to open anything aside of the initial internet browser that is being installed along with the system. Moreover, both DE's were mixed together when it comes to appearence. I also followed Switching to BSPWM from KDE as LordPoseidon26 suggested.

Guess the only way is to reinstall the system altogether.