Assuming that at the end of the day, I came away with about 30 million give or take...
DAY ONE after the check is in my hands - hire a tax lawyer, accountant, and probably an estate lawyer too. And then if possible, lie and say that I received a smaller amount than I did-- maybe 3-5 million, which is still a lot.
After getting my personal financial affairs sorted out, and most of it tucked away into investment accounts, I'd quit my job and give my closest friends 100k each and 50k to my good friends. I feel like that's enough to be generous and for a person to do a lot with, but also not so much that they'll wildly change their standard of living and then come crying to me when the money runs out.
For family... my mom would get about a million, my dad maybe half of that (he's got money and she doesn't), and I'd set up a trust fund for my sister for about half a million also. My grandparents would get any care they needed paid for. Reserve about 3 million for myself (that's an unimaginable amount of money for me already) and honestly... I might just go trawl the pages of sites like GoFundMe and YouCare and start fulfilling random people's requests-- for important things like surgeries, chemo, disability aids, things like that. The rest into conservation charities, charities that assist with training and poverty, and probably some political donations as well.
As for life changes, I honestly wouldn't change a lot about what we did/are doing now, at least not at first. In the long run, I would want to move out of our apartment, but I'd still want to keep living with my girlfriend and one of my current roommates. Maybe rent out an apartment or a house with a yard so I can garden, and a room we can designate a workroom for soap or crafts or art, as we're all pretty crafty people. Focus on my soap business on the side, as a hobby.
I'd eat out more-- maybe as much as 3-4 times a week, and tip like a madwoman when I do. I'd buy some fancier food ingredients and try cooking complicated recipes just because I can, and now I have the time. Travel more-- back to Taiwan to see relatives, to Japan, maybe stay there a month or two to just enjoy the sights, and go on the trip with a couple of friends. My big luxury spending would be trying out first class flights and going to fancy hot spring inns for a week, but I don't know if I would repeat the first class flight experience. None of this should add up to more than about ~25k a year (well, maybe not including the first class flight) so all the extra I'll funnel into charities or more direct donations to people who need it.
Learn new languages and skills-- car repair, armor making, Japanese, Spanish, re-learn my Mandarin. Read more. Hike more. Go to the beach more. But I'll be able to do all of those things after FIRE anyway, with or without a couple cool million.
When my current car gives out, I'll buy a fancy Prius with a back cam. Take my girlfriend out to a Michelin star restaurant at some point, and then hit up In N Out afterward.