There are lots of ways to find your purpose in your 20s. You can just sit down with a pen and paper and write down everything you're passionate about. Then, circle the things that keep occurring to you over and over. Those are probably what you should work on first.
Another way is to talk with people who've done what you want to do and ask them how they got started. They'll be able to give you advice on how to get started, as well as an insight into whether or not it's for you!