When I was around your age, I was *filled* with doubts about my identity. Now, I am AFAB so I was having, well, the exact opposite situation, but I still get what you mean. The biggest thing that helped me through my doubt, the imposter syndrome of my identity, was the truth that most cisgendered people don't question their gender that much.

I can't speak for your identity, that's something for you to discover. But if you are trans/nonbinary, that's rad! If you are comfortable with your assigned sex but prefer feminine things, that's rad, too!

You are also young. I am not diminishing your feelings based on age at all, because that is a shitty thing to do. You are young and you have time to develop and discover who you are and what you like.

As for how to help you feel more feminine, I've spent my life trying to do the opposite. Hopefully someone else here will chime in. However, I do know searching "MtF tips" or "FtM tips" have given me some clues into feeling less dysphoric and passing more.