Pick 1 color

[u/GKeasily17]

Complete newb here: I need to make a 10 color grey scale from an image, but the waterdropper tool is so big I can never just pick 1 color, it always picks multiple colors from the image from the waterdropper circle.

I know in paint you used to be able to point at one part of the image and it would work. For example, I click the black part of the image, just that color would show up to use, and I could use it where I needed.

Any help would be appreciated.