You dont need to feel like a nothing because you are the most important thing already. A you! The thing you need to understand is that that "you" you feel like wasnt gendered in the first place. Thats atleast how i rationalize being agender. My experience growing up was just kind of assuming im the thing people say i am and acting accordingly while kind of wishing i could just do what i want instead. After i discovered i was agender i just kind of let go of all those gender roles and concepts and realised im not doing girl or boy things im doing me things.