I'm 32 and in the *very* early stages of accepting myself as a transguy. Currently still going as birthname to pretty much everyone, though a good handful of my family and friends know I'm working through some stuff, questioning, some know I'm in therapy (not GT specifically yet because oi, there's a 12 month waitlist for that, as I found out on the day I phoned them up bordering on crisis levels of WTF) and a VERY few of them know my hopefully chosen name whenever I actually get up the stones to start openly transitioning. To all but one or two of my closest friends I have downplayed how deep this goes and how far along the spectrum I think I fall.
Growing up I tended to believe what science told me was objective truth, as well as trusting parents/teachers/other authorities to make rules and happily played within those boundaries pretty much (almost worryingly) without question. So having girl-parts meant I was a girl, and having to wear dresses for going out to "nice" events (and wearing a skirt for school uniform) was pretty much a given. I didn't know it was possible I could be anything else. I told people that "tomboy is an understatement" without really knowing what I meant, deep down. I dispised girly-girls as fake because I couldn't fathom why anyone would want to "dress up" like they were going somewhere fancy just every day.
There's so much I want advice about, but that probably doesn't all belong in an intro post.
I guess I'll end by saying this is as good a place as any to start getting used to using male pronouns for myself.
Cheers
J