Sorry, that guide was written for systems running systemd and the install manual you followed was a from an opinionated Arch user for SysVinit.
Oh, this guide is 11 years old written by someone who hated Wayland, so no, modern KDE won’t work with it.
Just use Arch Wiki, it’s the best for beginners, but also don’t install Arch unless you know what you’re doing already because it’s the worst for beginners.