Totally fair to ask! Only tricky thing for me, is it's kinda a bit of explaining the self to someone who has not had my life experiences, but I'll try my best. I find that being NB depends on the person, so here's my personal take.

Growing up I kinda had the classical trans case of hating my body and hated being referred to my gender at birth, and had no clue why. I chalked it up to self esteem issues because up until my grade 11 year, I was severely obese. During my grade 11 year, I lost all the excess weight.

After losing all the weight I still was still supremely depressed about my body and pronoun usage, and I had heard about trans people, but my problem was I thought I was insane for being super uncomfortable with my assigned gender, but not wanting to transition to the other and adhere to a binary that while it was better than my assigned gender at birth, still wouldn't make me happy.

Heard about non-binary people and it kinda just clicked. It proved to me I'm not insane for finding the gender binary uncomfortable, and allowing me the mental capacity to medically transition to be my ideal self.

I'm now 19 and decent happy, besides persistent depression issues, but happy nonetheless.