SNAP Processing Algorithm Locations

Hello, I am wondering where I can find documentation on how SNAP processes SAR (sentinel1) data. I am coming here from google earth engine because earth engine provides pre-processed sentinel1 data that has had the orbit file applied, thermal noise correction, radiometric calibration, and terrain correction performed. I am seeking to further understand what is occurring at each of these steps so that I may better know how the sentinel1 data was processed.
Thank you for your time-

You find the documentation in the user manual (Menu: Help / Help Contents).
For the most operations there are papers referenced which explain the details.