Do you have to register a business for a series in America?

As mentioned in my other question, I want to become a director where I've been helped well.

That's why I wanted to ask, so that I could gain experience early on, whether you have to register a business in America for your own series (for Netflix, Amazon prime, etc.).

I look forward to every answer.

That should be your least concern. You don't even get there, you don't get a work visa, nobody is interested in you, you don't earn any money and you live on the street like so many who had such ideas.

Could you avoid that?