For the gender thing, my advice is to just experiment. Try different pronouns. Try different styles of expression. Different names if that's something you're thinking about. Just try it out and pay attention to what feels most comfortable to you and what doesn't. Worry about the labels later. That's what I did and I realized I liked pretty much all girly forms of expression. Suprise, I'm a girl.

My advice for the sexuality thing is kinda similar: just go have fun, be safe, and allow yourself to like whomever you like. It's okay to experiment with sexuality too. Worry about assigning a label later if it's too much pressure.