Copy the Background layer to create a Background copy layer.
You'll edit the Background copy layer.
The Background layer remains untouched.
There are four (!) ways to make a Background copy layer.
Click, hold, and drag the Background layer onto the Create a new layer icon.
It's located at the bottom of the Layers panel.
Right click on the Background layer, and select Duplicate Layer.
Go to Layer > Duplicate.
Press Ctrl + j.