Take a look here:
KF 5 (KDE5) Start Menu
Windows 10 Start Menu
And here:
KDE 5 control panel with search
Win10 control panel with search
and the internal:
KF5 side tabs
Win10 side tabs
and many more…
like the notification, the personalization, the download from theme sites, etc. I just don’t want you to know me more from the screenshots. 🙂
Thus, if you are a KDE 5 user, you would found yourself familiar with Windows 10.
The End.