What you want to learn is a multiple field dicipline and you have to consult more than one source and work step by step. There is no package to learn it.
If you want some ressources feel free to contact me.
A paper that would help to better understand the relationship between GIS and soil :
Chapter GIS and Soil
For software tutorials, you have to choose if you want to work with open-source software or proprietary software. once you do your choice you can visit the official site of the software and you'll find all what you want to know.
Haroon Ilahi If you need more explanation feel free to contact me at [email protected]