Ender 3 Pro Firmware Original, and How Make Mods

[AlanSNV57]

I have a new ender 3 pro, the screen says Marlin 1.0.1, and has a date 2020-04-20.
It has a creality board V4.2.2

1. Is there a way I can get a copy of the original firmware so I can reload it if I mess something up?
2. It looks like HAS_RESUME_CONTINUE is configured, as M0, and M1 do not stop. I would like to add that in. Where can I get a copy of the configuration files used to make the firmware I have - ie the correct options for the type of thermistor, correct stepper drivers etc.
3. Any good tutorial on how to build the marlin software on windows? My first attempt resulted in:
   C:\Users\alans\Marlin>make
   make: *** No rule to make target applet/wiring.o', needed by applet/Marlin.elf'. Stop.