BEFORE YOU ASK
Before you ever ask, it learned from a lot of reading.
Long before your question, the model was trained on an enormous amount of text: books, websites, articles, and more. It didn’t store it all like a library. It learned patterns: how words, ideas, and facts tend to fit together.
It’s a bit like: Someone who has read millions of books and absorbed how language works, without keeping a copy of every page.