If you don't already have it, how do you find your Purpose?
First, a secret: despite what you might think, everybody else doesn't have it figured out and you're the only one who doesn't. Start there. Everybody is on a journey of discovering and living out of their Purpose. Some are just further along that others.
Second, Purpose is deeply tied to who we are and to the things we care about. If you haven't already done this, take note of the things you like and love. And be honest. Don't note things you think you're "supposed" to like or be passionate about. If pigeons and paper clips are your jam, own it!
Third, think about why you love those things and what about them tickles your fascination?
Another way to do this is time-travel. Your childhood self knows a lot more about your passions than you remember. Go back and think, what did you love then? What did you "want to be when you grow up?"
These interests, passions and fascinations are all hints and clues to your Purpose. Your most authentic and satisfying purpose comes out if who you are. But you have to know what you're interested in and what your good at.