As a medicated ADHD adult, I struggle with this, too, because someone who asks this may be looking for specific aspects of your personality, or hobbies, or literally anything not related to what you may be thinking or worrying about at that moment. So make it a point to put the ball back into their court:

"Sure, what do you wanna know?"

IME: if they don't know what to ask, then they likely don't actually care, so apply the K.I.S.S. principle and pick one not-interesting thing. Not your circus, not your monkeys.