Transparent Background for export

So working on an entire homebrew world map and it has a lot of stamp making loading it run slow even with using shapes instead of trees to cut down on the stamps. Well I can cut my world into 3 major continents so everything stays editable and loads faster. Then using custom stamps or photoshop I can combine the world into one image and replace sections when I make an edits to areas within. Problem is it’s a fantasy world and there isn’t one color I can tell photoshop to select to delete and make transparent without deleting details in the map. So being able to turn the background transparent then export would greatly speed up my work flow and others would probably find uses for it too.