Draw a small grid

Then use a mask.

commander

Draw a square

Right-click and drag the picture.

Accurate image editing

then

Ctrl click

Completed after repositioning.

Appendix (Postscript)

It should be a mask, but I can't think of what it is at once. .

Anyway, it was achieved by a mask.

There is a stupid way to achieve it.

Draw a white rectangle like the page and grid it.

Then draw a small grid

Small grid merging graph

Hold down the Ctrl key and click the image in the Layers panel to select pixels.

Then switch to the white rectangle layer and delete it.