Today we hit three bit topics when it comes to making landscapes automatically look nice:
1) Having UE5 apply a different material to your landscape based on the steepness of the land there
2) Using material functions to import a material into another material
3) How to add layers to a map so you can paint a road on the map (and a common bug in UE5 when you do this)
4) How to make a layer of your landscape automatically output grass to that layer, making meadows and dead grass patches, etc. appear without having to manually paint them onto the surface.