Hey, trans/nonbinary person here.
I don't know how old you are, but back in like 2012 or so there became a big craze of LGBTQ people making "It Gets Better" videos. I'm not going to say it does, because it doesn't necessarily, and even if it does it often takes a lot of hard work. But I do feel an important message is does send, that IS accurate, is that your reality right now will not be your reality forever.
Suicide and self-harm are an option for people who often don't see a way out of their current misery. I know for me there have been times that misery has seemed to stretch on and on. I don't know you, or your exact situation, but I can see you are hurting, and I can identify with the pain of not living life as you truly are. You will not always have to live under your parents' thumb. One day, maybe not soon but one day, you will be on your own, and you can live as the person you truly are. You can, and most likely will, find supportive people who understand what you are going through, and you can build a sense of family and community with those people. I call those in my life "chosen family," and they have saved my life, over and over again.
Do not the lens of your parents and teachers and other kids at school color who YOU know YOU are. I cannot stress this enough. At a time I was really, really low someone told me if you live for anything, live for spite. Do not let others lead you to take yourself out of this world before you ever even get a chance to live as yourself in it. Do not let them make you give up. You may not see it, but you are perfect as you are, and you are worthy of love as you are. I mean that 100%. I imagine those words feel hollow. I know in my darkest times people have told me that, and I basically scoffed at it. But given time, I found it was true. I find and lose that thread again throughout my life, depending on my mood and circumstances, but when I am at my healthiest, subjective and objectively, I know it to be true. And it's true for you, too. Every person deserves a chance at living as their true selves, even in a world that seem hopeless, that seems to discourage that. Give yourself that chance.
Perhaps, if you feel it to be right, that can be your longterm goal: to live life as you are. In the meantime, something I've found helpful is finding one small thing positive in each day. Even when I am feeling overwhelmingly negative, I have managed to find at least one tiny thing that didn't suck AS much as the rest of it. Maybe you see a pretty flower outside. Or maybe you saw a stranger wearing an outfit you thought looked nice. Maybe you took a few minutes to listen to your favorite song, or ate a food you find likable, if not enjoyable (I know depression can make eating challenging sometimes, so feel free not to necessarily rely on that one). But you catch my drift. One thing. Even if it's not so much a "joy" and more of a "sucks a little less" kind of thing.
In the meantime, please look into The Trevor Project. It's a suicide hotline specifically geared toward LGBTQ youth. I also suggest, if you have the means to do so, looking into some peer groups, or maybe even support groups, for LGBTQ youth, either in your area or online. If you don't have safe access to a computer at home you can always get on one at school, or perhaps on your phone. I believe The Trevor Project also has a button you can click to quickly clear the page if you're on it and someone comes up behind you or otherwise interferes with your privacy and you need a quick escape.
You are not alone. There are so many people out there, feeling adrift, alone, and empty, like you report to be, thinking they will never find anyone like them. But I have found that life has a funny way of bringing such people together. And once you find them, you'll be damn glad you never gave up on yourself. And they'll feel that way, too.
Take care, and don't hesitate to
PM me. I am always happy to listen.