net user
obs, flameshot/sharex, and 7-zip
pipepipe and rimusic is what i use. youtube in the browser is fine too, if you disable that “open in the youtube app” popup (firefox for android with ublock origin addon is what i use, although i have experienced some regressions with the ad-blocker not working after youtube updates something, but ublock is usually on top of it and fixes stuff quickly).
It would be great if Plasma gets a kiosk mode option some day, that seems right up KDE’s alley as far as the “simple by default, powerful when needed” philosophy goes.