Disclaimer: I am new to Godot.

Basic Information:
Godot 4.4.1
Using TileMapLayer

I am making a custom tool that allows me to write terrain. When I load the terrain using the tool during runtime, the terrain looks really flat. the terrain has unknown number of layers. The tool creates TileMapLayers during runtime and each of the TileMapLayers are an elevation. TileMapLayer 0 is the ground, TileMapLayer 1 is an elevation of terrain by 1 unit as so forth. I want to add shaders or normal maps to be able to tell the difference in elevation.

The pictures below shows the problem, the terrain looks flat but there is elevation in terrain. I want to add depth, shadows, normal maps, or anything else so that my terrain does not look flat.