I'm not sure I fully understand, for most use cases you can just download the main Modern Interiors folder which contains everything in the Modern Interiors pack.
If you're using RPG Maker there's a separate folder there for you which has been modified to work with that engine specifically.
The Character Generator is a tool (Created by me) which makes creating characters easier, in the main Modern Interiors folder there are characters but they are all split into different parts which you need to manually combine together, the Character Generator is simply a software to help you create characters without having to go through that process.
Hope I understood your question correctly and was able to answer it, let me know if I miss understood the question.