If you are planning to be employed, it is probably easier if you have at least basic credentials like a high-school diploma and secondary education. You might be able to make up for it with a really impressive portfolio, however, it will take time to put that together.
If you are planning to create a business or freelance, all you need to do is acquire the skills and sell them. Clients really don't care about your formal education as long as you can do what they need.
