What don't you want? As a companion to the "What do you want?" post. I like to flip the question the other way when someone says they don't know.
Well, would you like to wind up having a short life, due to poor health? If the answer is "no", which I hope it is. Then, the flip side is you would like a longer life in good health.
Would you like to be poor and not be able to support yourself and or others? If the answer is "no", which I hope it is. Then, the flip side is that you would like to make enough money to support yourself and perhaps others.
I have talked with several teenagers and early twenties individuals who say they don't know. But, they do know they would like a nice car someday, perhaps a spouse that would need support, and have some money to go places. Then, what would they have to do to get money for those things? Good nutrition and physical ability provide options like money provides options. What would it take to have better nutrition and physical ability? Having options, to me, is having power. Knowing what would provide more power becomes the start for making some goals.
Looking at these flip sides is a great way to figure out what you do want, if you are not sure.