Ask HN: Which large tech company will best prepare me to be a startup founder?

- I'm soon to graduate from university.

- I want to go into big tech for a few years as a software developer to do things like knock out student debt fast and have a secure job as I find my feet.

- I also know that I want to found a startup a few years later.

- Of the big tech companies, which cultures will help prepare me for this role most? Why and how?