I don't feel like a normal teenager what should I do?
I am literally exactly the same, over time and surrounded by the right people you just realize there's nothing wrong with it. But some actual advise is to be the best version of yourself, if that's you now then please make no changes, but if it's not i suggest really pushing yourself to try new things and step out of your comfort zone.
Learn to love & accept yourself as yu are mature for yur age this is a good thing none of us are cmpletely "normal".
Act like yourself. Nothing wrong with wanting to be informed about the world, well-read, and well-groomed. You may feel like an oddball now, but you're just hitting your groove and figuring out who you are earlier than most people your age. I've met a few kids like that (like the 8 year old kid of a friend of mine who is already WAY more into gourmet cooking than most adults are), and they usually turn out to be pretty interesting people. Have some confidence in who you are and what you like, don't apologize for it, but also be understanding that other people will like much different things and that's okay, too.
Just be you. If anything, it's rare to find a guy your age that actually KNOWS how to use complex words properly. Not only that, it'll help you in the future when you're applying for colleges, jobs, and internships. You're not strange, you just mentally(?) matured faster than any typical 15 year old boy. That'll take you places in the future.