You can get a lot on the internet for free. I truly believe you can attain 80% mastery in any field with information freely available online.
Why pay for anything then? Time. Free content is plentiful, but it's fluffy. You have to wade through a lot to get to the gold nuggets. Paid material like courses cut straight to the point.
You have time and you have money. In the beginning, you have more time than money. This means you can spend the time wading through the free content to find the gold without paying. This is smart to do.
If you have more time than money, go deep on your specialty. Do your research, find and exhaust the best free material out there and learn from it.
Here's the top three highest value materials out there that are easily accessible:
1. Podcasts
2. Videos
3. Books
Most of these are freely available. There are podcasts on every topic that can teach you more than you'll learn in college. There are tons of free educational videos on YouTube and also ebooks, or books freely available at your library.
Eventually though, if you're growing, your time is worth more than your money. Eventually you have more money than time. There comes a point where you're wasting money by wading through free content. If you don't learn to recognize this point and start buying time with your money, you're actually losing money.