I like to keep my plasma desktop as close to my win 11 desktop as possible, more for consistency than and personal preference. Here are a few tips:

There are a few decent Windows 10/11 plasma themes. I would stick with the breeze window decorations though because the 3rd party ones often don't scale properly.

Change the icons. There are a ton of options that would be more windows like. Consider changing the cursor as well. I like the breeze cursor but it screams 'this isn't windows!'

The default start menu is a little weird. I typically change it out for the one that looks more like the Win9x start menu.

You can change the click behaviour of the task bar to behave more like windows.

Personally I find the gnome file browser a little more user friendly than Dolphin, so swapping that as the default file browser might be a good idea.

OnlyOffice is an alternative to LibreOffice that is a little closer to Office