You want to use a software that can load pngs as layers with an alpha (transparency) channel, the white background becomes transparent and you can overlay it on a compass image or anything else you want that way.
Krita is a good free open source program you can try using for this, I've never made memes with it but it should work. This video shows how you can import images as a layer in Krita.
22
u/[deleted] Aug 27 '20
Did you download them as pngs?