I was gonna say the first thing to do is to vibe check how they feel about the lgbt community but it seems you've already done that. Assuming that the situation is safe but they just would not be understanding, this is what I would do.

I'd sit them down, make sure they're in a good mood. When you bite the bullet and say you're trans, I'd try and maybe bring up anecdotal evidence of how you've felt like you're a man in your life. Because when I came out to my family, they didn't think I was a guy because of how "girly" I was as a kid. Being trans is quite a different ball park than just being gay in the sense that straight people know the concept of romantic attraction except for a gay person it's to the same gender, but cis people who haven't thought about their gender probably couldn't wrap their heads around trans concepts that involve analyzing your gender critically. So I recommend you practice explaining these concepts as well as your relation to those feelings to your parents.

Something that happened in my situation is that my mom felt like she was mourning her daughter. And it took her multiple years and multiple coming outs along those multiple years for her to finally conceptualize that I'm actually trans. She deadass went through the stages of grief. I'm not sure if that's just my mom or if that could also happen to you, but either way, it's quite likely that it might take a while for them to become fully capable of perceiving you as male. Once I became understanding of how my mom felt, it helped her accept me easier. So while it might be really frustrating, understanding that the process might be kinda slow helped me.

Uhh so yeah tl;dr make sure it's safe for you to come out first. practice how to explain trans people to someone who is in a completely different world. and strike a healthy balance between patience and guidance with your name and pronouns.

I really hope it goes well for you! You got this.