Seems to be a gap in my knowledge about terrain texturing

I’m missing something to do with the terrain, I cant seem to achieve this realistic look that you see in the last two images. If you look at my image, and disregard the rocks and foliage, you will see that the terrain is very flat, there’s not much of a gravel or sand texture about it, no little rocks or small details that would make it look realistic, there’s no variation, and the texture is tiling. I don’t understand how I can get it looking like the other images. Am I just supposed to completely spatter the terrain with foliage and rocks to hide it? In the example images, I see tons of variation, cracks, rocks, clear tracks in the dirt etc. This is for a work project (hence the black boxes) and I often miss out on projects like this because I dont quite understand yet how to achieve this look yet. Any help would be very appreciated.