The MPCNC is used by many people using different tools and having different setups. There is no one-size-fits-all answer to your question. Good answers will depend on your pipeline, on your current abilities with your tools, and how’ve you setup your machine. The chart at the top of this topic gives a good overview of the various choices you can make on the software side. A common choice is:
- Some drawing program
- EstlCAM
- Repetier-Host
Personally, I use Fusion 360 and sneakernet my g-code to my machine.