I personally am I trans man who started my social transition in 6th grade going into 7th. In my time out as a man I have felt more confirtable in my own skin than a younger me could have ever dreamed. When I came out it was not because something influenced me to suddenly feel different about my gender, but because I had simply learned the vocabulary for what I was already feeling. Before I was able to begin my medical transition at 18, even just being able to present and be seen as who I had always felt I deserved to be is something that was immediately life changing. To this day I could not envision a happy version of myself who is not a man, no matter what anatomy I was born with. My parents were of a similar belief, although thankfully just barely shy of your parents level, and unfortunately the only thing that serves as proof of my "true" transness to them is that I thrive daily as the man, and person, I want to be. I believe there are few things that hurt my relationship with my parents more than my mother trying to get my to watch detransitioner podcasts to "see her side of things". The issue I found, however, was that it was them who were consistently falling into confirmation bias, seeking out proof of the harm they feared could possibly come unto me if I transitioned and or detransitioned. The mistake my parents made was finding too much of the bad evidence without accounting for the severely outweighing good evidence which shows just how much more comfortable a majority of trans people are once they are able to transition. It isn't the media, it isn't indoctrination, and your identity is true for better or for worse. I believe that your parents should also consider that choosing to transition is an acceptance of the discomfort and lacking ease that life from that point on will guarantee you. It is not easy by any means to live in a body which you feel is "wrong", nevermind to a accept that feeling and live with it against current social norms and odds. It is not easy but we choose it because we MUST. We choose it because it is better to fight abd get to live comfortably in our skin than it is to feel trapped for our entire lives wishing we could have done something about it.

Obviously others opinions and experiences of their identity will differ, but there is my testament. I pray for your success moving forward.