Windows 10 - File explorer and other apps acting weird

[BitterB]

Some friend of mine was messing with my laptop, and now when I open file explorer or something originally from windows, this is what it looks like. How do I fix it?

 

[davehc]

Lol. Sorry about the late reply. I was half expecting a frequent member to step in.

Open the settings - Personalisation
Click "Start"

Open this item

There you should find all the customising items you are seeking.
If you are unable to work it through, please post back
You could make a good start by just clicking it to Off

 

[Regedit32]

What precisely is it you want to fix?

The Dark theme, or as @davehc has already pointed you to, the option not to display recently opened items?

 

[BitterB]

It's okay now. My friend has fixed it. The problem was the white bar at the top of the app. It would frequently change colours from white to yellow to blue, and make it almost impossible to read the alerts that I was receiving. But as I said, it's been fixed, but thanks anyway for replying

 

[davehc]

Ok. No prob. A more detailed explanation would, of course, got a quick solution!!