Thank you for your openness and honesty. Because of your age, just know that there's no pressure to commit to an identity just yet. In a few years, you may very well feel like you suit a more feminine presentation, or you may continue to feel like masculinity represents you best. And that's ok - it's ok to be fluid and not know who you are yet. At 17, I know that I was still coming to terms with aspects of my own identity, like my bisexuality.
To experiment with your gender expression, I'd recommend asking a few close friends or family to start referring to you using he/him/his pronouns (or others that you may like) and/or with a different name that you feel represents you better than your birth name, and see how that makes you feel. It's a good way to start exploring your identity and playing with the idea of identifying with a more masculine presentation.
I would also encourage you to look into neogenders, as you may find comfort in some of these labels/pronouns. I would also try not to worry about how you are perceived by others, or perhaps seek out a community of trusted friends and/or family who feel comfortable with you expressing your identity however you would like. There are plenty of clubs and online chat forums (like Discord) where you'll find likeminded individuals in your exact position. You're definitely not the first person to feel like way, and you certainly won't be the last.
With regards to your physical appearance, I know that most adolescents tend to have an uncomfortable relationship with their appearance, so that's totally normal. I'll quote one of my favourite sayings, "your appearance is the least interesting thing about you", meaning that there's so much more to a person than just what they look like. Don't let your appearance define you, but let it be an expression of the person you are. I understand that with gender dysphoria, it may be helpful to experiment with your appearance and opt for a more masculine presentation, and I'd say go for it. See what feels natural for you.
I wish you all the best in your gender exploration, please let us know how you're feeling about it all! We're always here to talk more if you need.
Best wishes, SB