We’re eloping!!

So we have been through hell since we announced our engagement. Long story short my mom has done basically everything in her power to try to make me postpone and I’m very honestly done with it. So we are doing the big ceremony later and getting married at the end of may/early June. That being said, has anyone gotten married at a park? If we were to do this what would we need to do for it? Do we need to call the park and book or can you just show up? Flip side to that— have any of you done backyard elopement/weddings? I’m just so lost as to where to go from here. Also any Amazon and Etsy must haves, include links below❤️