Whether you're gay, lesbian, trans, or non-binary, if you want to know if someone will support you, all you have to do is ask "What are your thoughts on X?" If they say something along the lines of "they're too young to understand because they haven't lived," or the typical "fuck you, sky daddy forbids it and you'll burn in hell," then you know who to cut out of your life.
My dad used to be a pretty intolerant person, according to mom, but he was very accepting when I came out to him. All he said was that as long as I was successful, he didn't really care what I did. He even said he would educate himself on the matter. My stepdad, on the other hand, someone who I thought was tolerant happened to be the first person to basically say my feelings and identity were invalid because I'm too young to know how I feel. I can't remember the last time I went mentally numb so fast.
I know how I feel, the feeling has been there for years, I'm not faking it, go fuck yourself.
Keep people who support you, or at the very least respect you as a person even if they disagree with your choice, close to you. I speak only for myself when I say it's better for someone to say "I disagree with your choice to transition because it's against my belief (it's usually a Christian saying this in my case), but I still respect you as a person." In other words, "live and let live."
You have the power to choose who to get involved with, especially if you're independent. If you live with your parents and they're supportive, great! If they're intolerant, at least try to find a support group or online group chat or something. I found a Mastodon instance of LGBT individuals. There are Discord servers ran by and for LGBT individuals, but I won't link the one I'm in since it's meant for locals.