I'm currently using Ubuntu 17.10 and I recently installed Kubuntu Desktop to get KDE, the installation succeeded, but my PC got messed up as it installed dozens of applications, modified the boot configuration and start screen that made my PC run a bit slow. I finally uninstalled the Kubuntu Desktop and the applications that came with it. But I liked the look of KDE Plasma, isn't there any way to install just the KDE Plasma and not the full Kubuntu Desktop?
As DK Bose said, I tried executing this command:
~$ sudo apt-get install plasma-desktop
And voila, it worked! It certainly does. It neither installed full
kde-desktop, nor installed any more annoying apps nor modified my bootup configuration. I'm now using KDE without any problems, and the best part is my PC doesn't slow down.
Thanks to DK Bose and the Ask Ubuntu community who put efforts to solve my problem. I appreciate their efforts.
sudo apt install kde-plasma-desktop
Keep in mind this will not install any Kubuntu apps so you'll have to use your OS's own ones. Also if you're not prompted to change your login manager, do:
sudo dpkg-reconfigure sddm
Personally, I would change the login manager to sddm as to me, it looks a lot more attractive but you can change it to whatever you want.