Here's an interesting little tutorial about how to set up and use KRunner (hint: it's easy) which is automatically installed if you have KDE Plasma. It's an easy way to access terminal functions and more without opening a terminal. Taken from the article, here's what KRunner is capable of doing:
QuoteStart and stop applications.
Install applications.
Run commands.
Open web pages and bookmarks.
Search for (and open) files and folders.
Switch sessions, windows, desktops, and activities.
Access contacts (for easy sending of emails and more).
Play music from the default music player.
Calculate short equations.
Display the time and date.
Check the spelling of words.
Manage your computer settings.
And more.
https://www.zdnet.com/article/kde-plasmas-krunner-is-a-handy-tool-how-and-why-you-should-be-using-it/?utm_source=pocket_saves