Tips on importing Geo map data? Really confused!

Hi friends. I’m new to using Gaea. I’ve been watching hours of tutorials and I actually kind of get what I’m doing. But I wanted to try using real geographical map data. This has been extremely challenging and I have had no success unfortunately. I’ve used both US GIS web source and also European Copernicus data, but no matter how I import it into the program, it comes out as a flat white plane with nothing on it. Wondering if anyone has a guide on how to get set up doing this? It seems like it should be very simple.

I basically go to my chosen GIS platform and find a small area, like 8 km for example, export it as DEM, digital elevation map, and make sure that it is a tif output. For Copernicus however, it seems that it exports it as a .tiff, with two fs. I’m not sure why that is. I was able to drag it into the graph but not able to find it in the import menu

Curious if anyone has tried with real elevation data and this is what I really want to learn because I think it’s so fascinating