How do I undo a mistake I just made?

You'll be able to: Undo accidental changes across apps and files

The steps

1
Hold the Ctrl key on your keyboard and press the letter Z. Your last action immediately reverses itself (erased text reappears, or a moved file returns to its folder).
Where does Ctrl + Z work?
CtrlZ works in almost every Windows software: Microsoft Word, Excel, web browsers, photo editors, and even inside File Explorer when moving or deleting folders.
2
If you need to undo multiple mistakes, press CtrlZ repeatedly. Each press steps back one previous action in chronological order.
3
If you pressed undo too many times, press CtrlY to redo. The computer steps forward again and restores the action you just undid.
Tip
Undo only works while the application is still open. Once you completely close a program, its undo history is cleared.

It looks different on my screen

Some programs also have a curved arrow icon pointing left in their top menu bar which performs the exact same undo function when clicked.

Did this work?