Advice about the type of organization to be set up in Germany

I need to understand the best type of organization to set up in germany. Currently, i am a consultant with a small company (). I would like to kwn the best option for the upgrate such as GHmd or other options. I also warned to know how to set up a comply with external investment come from investors from China. And finals, which are the option to set up a company with a foreign partner in Germany. How to know the foreing fund and invest money is clean money.