It would be really cool if lgbtq+ people could help with this slight problem for me. Sorry straight people. I don't have anything against you all but unless you've helped someone with this I don't think you can be much help.

1) how do you tell you mom your genderfluid and pan on top of being ace. How some might think "ok it's just there mom. How hard can it be to tell them this?" Or " oooo. This might be hard if there mom is homophobic and doesn't support. " but it's quite different. My mom is supportive but I find her extremely intimidating that when it comes to stuff like this I find it hard to tell her without chickening out. Also the last I told her I was ace she said that I'm probably doing this to get attention and it would be wiser to determine this stuff out when I'm older and all that stuff while also being supportive.

2) how do I tell my grandparents that I'm genderfluid, pan, and add and then explain what it all means. My grandparents are also good Christians to with my grandma being significantly less intimidating then my mom and my grandpa being significantly more intimidating then my mom (probably doesn't help that he was also in the navy either)

How my aunt's and uncle I don't have to worry about because my mom and aunt tell each other everything so my mom would tell my aunt this and then my other aunt and my uncle I don't see to often do I don't see it as important to tell them.

The main thing I need advice on is how to tell my mom and grandparents without getting nervous and chickening out.

First of all, you don't NEED to tell them. It isn't a requirement. Only tell your family if you WANT to. But I think the best way to do it would be in not a really serious situation. Don't overdo it. Make sure that you're relaxed. Then just tell them. I can't really tell you how they'll react, but the worst case scenerio is that they don't accept you. And if they don't, you have a whole community who does. If they do accept it, just make sure to do your research. Be prepared for whatever questions they ask. If they have a lot of information on what's going on, then they might be more inclined to try and help. However, if all else fails, just don't mention it to them again. You should be able to be yourself without worrying about what your family thinks