Founding a startup. Who is the best to talk to for information?

I am thinking about starting a new company and am looking for some help regarding costs, legal requirements, etc.

I have taken a look at the JETRO website, and I think that’s a good starting point. It seems straight forward enough to “establish” the company. But I still have questions around how self-funding works and avoiding double taxation, hiring employees, tax and other obligations when dealing with employees, and so on.

Is it best to just go straight to a business accounting firm? Or are there organizations dedicated to helping and answering some of these questions?