In this project I use the esp-idf along with a LoRa esp-idf component library that was originally ported from Sandeep Mistry's arduino LoRa Library. The link to the component library is here.
I also use the ssd1306 component library from here.
To set up, you need to copy the "lora" folder and the "ssd1306" folder to the components folder in the esp-idf directory. then copy the LoRa2MQTT folder to "examples/protocols/mqtt/ folder.
then do the install.bat and export.bat scripts to ensure the "lora" and "ssd1306" component libraries have been incorporated in to the system.
Then open the esp-idf command prompt and navigate to the the project folder "$ESP-IDF_PATH/examples/protococols/mqtt/LoRaMQTT".
Then run idf.py menuconfig if you want to make any changes, but otherwise do idf.py -p [COM7] flash monitor.