Select the area where you want to add points, and right-click in the selection-by copying the layer (or you can copy the layer by ctrl+c first and then ctrl+v).
2.
3.
Change the foreground color to black and open the filter library.
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5.
Click on the sketch-click on the halftone pattern again, adjust the parameters and confirm.
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7.
Then adjust the parameters on the layer, and it's done.
8.
I gave an example:
Or, you can create more effects by changing all the colors in the foreground and background: