How does a college freshman get into startup culture without technical skills learned in upper division classes?

Is working at a start up a viable path for college graduates or is it recommended starting at a more established company?

Do you see Silicon Valley maintaining its dominance as a tech capital in future decades or will there be better entrepreneur ecosystems?

Which industries are ripe for entrepreneurship? Like the automobile industry at the moment has innovations of self-driving and electric energy source.

Thanks!