Clone this repo to your PC. Create a new project with PlatformIO (also available as a VSCode extension), name it "HeatControlBox", select "NodeMCU 1.0 (ESP-12E Module)" as board and "Arduino" as framwork. Then remove the mark at "use default location" and in the bottom window navigat to the folder containing the cloned repo.
\ Done! Now you can should be able to plug your NodeMCU to your computer and flash the program onto it.
Wiring diagram will follow!