Step 1:
Open the image in GIMP
Ctrl + D to duplicate the image
Right click on the image → Colors → Components → Decompose
Change the color model value to LAB
Step 2
After completing the step 1
Right click on the image → image → mode → indexed
In colormap options select "use black and white (1-bit) palette.
And click convert.
This will help you to print files from photos.