Find a method you want to change (e.g., TakeDamage() or PlayerMovement() ).
If the file is actually a mod package for Skyrim Special Edition on Nexus Mods : You will likely see .esp , .esm , or .bsa files. Shadow.of.the.Guild.rar
Use a tool like WinRAR or 7-Zip to extract Shadow.of.the.Guild.rar to a dedicated workspace folder. Find a method you want to change (e