gender is not scientifically able to be measured in anyway
i.e. not real.
It's not that the concept is confusing, it's that it's not true. There is no such thing or quality in the real world as "gender" as distinct from "sex".
If you're going to use words scientifically, they need to actually describe something that is in the world and not just in your imagination. BTW, I don't care at all if a man wants to wear makeup and a dress or if a woman wants to take testosterone and grow a beard. People ought to be free to live their own lives the way they see fit. But in that same vein I'm not going to be forced to accept as true something that is clearly and fundamentally false.
IMO (not that you asked) this issue is being used to divide people who are committed to the truth from people who want to be nice and accepting, and we shouldn't allow ourselves to be manipulated like that.
That's all I have to say about it. Have a nice day, and I wish you well.
edit: One other thing I have to say is that being nice and accepting is a good thing, and that people who consider themselves trans ought to be loved and respected just like anyone else. To the extent that there are evil people who wish them harm, god willing we would have the strength to stand up and protect them.
https://www.youtube.com/watch?v=-XNFokmDKrE