Hello, this is my first post on this site. I hope I'm posting this in the correct category; I am under 18 after all, but I feel like this post is all over the place

Lately I have been feeling extremely out of touch with everyone else and losing my motivation for friendships, school, etc. I'm losing motivation: I can't picture a future as female at all. I feel like I'm not really living how I want to live and I'm wasting all my time because I'm not living as a male. Am I alone on that, or can anyone relate? I want to start medically transitioning but I have only told my older siblings how I feel and I feel like I'm not getting anywhere because I haven't told my parents what I want to do. I have told them how I felt in the past a few years ago, but I guess they didn't take me seriously.
I go to one of the top high schools but I'm rapidly losing interest in my grades because it feels like it doesn't matter anymore. I can't relate to any of my friends anymore; I have to put up an act for everyone. Mostly I wonder how everyone else can seem so content and optimistic with themselves. I guess that could be teenage angst, lol, but I have been feeling that way for a long time now. I really want my chest gone and I dread the thought of any further development of secondary sexual characteristics. I've been feeling very anxious about my hips getting wider.
Can anybody else relate to me? Or know how I can at least feel more connected to my current reality (that probably sounds confusing...)?

How can I stay motivated for the time being, until I can get the courage to officially come out?