Issue with tile sizing

So I have a project which involves me transferring accurate world height maps and putting them into my project at the correct scale, my issue is when I do this and scale the map properly (which by the way is enormous, I still get baffled by how big this section is) the tiles if that’s what it is, or easier said, the small squares which make up the map are no longer small, in fact, they are bigger than the Player when walking around is there any possible way to make the smaller, I guess this would up the resolution of the map (Honestly don’t know what I’m talking about so feel free to correct me if I’m wrong), any advice would be much appreciated.