Can Someone Explain This To Me?

[Amarok]

So I was thinking back to a comic on a Truth For Youth Bible I read as a teenager, well I was 14 so teenager is a light term, and a thought came to mind.

I rather liked the comics, despite their horrible message and stupidity, it kept my attention with the art style and colors. And the magical one just had me laughing my ass off at how this idea, outside of the fact it's just stupid, would male for a humorous Netflix original. But on topic again, the one comic that had me scratching my head was the gay comic, with the usage of gays using the term 'Born This Way'.

Now, I myself am asexual, in a sense I don't like the idea of sex, but I also like both men and women in the dating category, took a lot of flip floppy for most of a teenage life to understand that. So I am not trying to dis on any of this, but it's a question that has plagued my mind for a while, and tends to cause me to go in circles.
But, when I heard many LGBT people using the term 'Born this way'. I always found myself very confused on the meaning of the words. 
I never understood how a person is born gay or bisexual, or transgender, or lesbian. I guess it could have something to do with chemicals, but then again straight people do say they were born straight. Much less I don't understand how you can tell how you were born, as most babies all look the same to me. Small, squishy, and with big eyes that rival my black moor fishes. 

I guess you could call it a choice, but that doesn't feel like the right word either, as some people do like men and just can't be turned on my women. So it would then translate to that you were born with the chemical thought pattern to look at men rather than women and vice versa. 
Then the transgender thing just makes it more of a headache, but I guess it could work in the same sense born with a different chemical balance than others Though saying it like that makes it sound like they have a mental problem, that is territory that just is more of a headache than this.

Anywho, anyone have any idea how to make sense of this. Or just to laugh at Truth For Youth comics also, because that's fun too!
((And please don't take this as me just being a bigot, I'm not trying to be that, but when I try and ask with question most call me homophobic. Clearly, I'm not a homophob, I'm just asking an honest question to get a clearer answer. Which, it hard in this day and age, because people get triggered over one trying to get clear answers. Almost like that want you to be oblivious.))

By born i think they mean that it developed the same way as being straight