how do i come out?

i mean, my mom n step dad think me having a girlfriend was a phase and they talk about how trans people are mentally ill all the fucking time (them also say they'd support me no matter what)

I guess I want to tell my mom about how, for the past like 3-4 years of my life, I've known I'm enby and how I prefer going by he-him they-them and want to be called Ezra. I want to socially transition and not be seen as a girl. i want my mom to know my "best friend" isn't just a friend. that I love him and how he's supported me through thick and thin. I want her to know I go to bed at night thinking, "How do I make my chest flat?" I want her to know I'm NOT a little girl. I want to be able to tell my dad who I am,  I want to change my name in school. I want to be happy with who I am and who I'm perceived to be. 

also how does one tell their parents who think hellnistopc polytheism is crazy that they are infact a helpol worshiper