For a while now I've been thinking about coming out to my family as non-binary. I know I'm fortunate enough to have parents that MIGHT accept me. But they've talked before about not being very supportive of the lgbtqia+ community and I'm worried about coming out. Is there any advice I can get? I'd be super appreciative :)

I'd talk to them about how they feel about Non-binary people and try and educate them about it before you come out. It can give you a better Idea of how they'll react and maybe help them understand better.
I hope this helps.

Hi. I'm a trans man, so I've been in that situation before.
If there is any concern about them being supportive, I really do advise being in a safe environment away from them or at least having somewhere you can go away from them if things turn bad.
As for actually coming out, just do whatever feels most comfortable for you.
Personally, I knew for sure I wasn't cis at 14. I didn't come out to my parents until I went away for college at 18. I messaged them in a group chat and explained to them how long I knew, what it meant, what name I preferred, and that I just wanted their support.
My dad is a super neutral guy and always told me that as long as I don't do anything stupid, he'll support me. Coming out to him was no different, he kept that same attitude. My mom, however, reacted badly at first, and it took her several months to come around. But now she is super supportive of me.
I'm really glad I waited until I was away when I came out, cause it gave all of us space to process and understand. I wouldn't have done it any other way.

I do agree with D that talking to them about nonbinary people can help. Maybe mention a nonbinary celebrity? I know a few months before I came out, my family watched the Survivor episode where Zeke Smith was outed as trans and their reactions gave me a good sense of how supportive they'd be and gave me more confidece in coming out.

I wish you luck in however you choose to come out and hope your parents will accept and support you! :)