I'm not entirely sure what you are asking but I'm guessing it has something to do with how do you validate whether what you learned is correct or not.
I consider myself something of a self-learner and I always find some way to put what I learn into practice. Sometimes that means building something, physical or virtual, either one works. Sometimes that means discussing it with an expert.
Nothing teaches where you are misinformed or lack understanding like putting your knowledge into practice.
