Hot to make it more realistic, hq (material)

Hi, today i decided myself to learn make a better materials, as in the pictures. Can somebody tell me / show me how to make it very beautiful and high quality?
Heres the link with the pictures, and where i donwloaded the textures.

Pictures: UE 4 mat q&a - Google Drive

Textures: Brown Mud Dry Texture • Poly Haven

Thanks, have a nice day!