Disclaimer: I can’t vouch for the ethics or practices of some of these, and definitely not of the people you might meet on them. Always use care with any app or website that connects you with people, and don’t send money to people you don’t know.
FetLife.com: Has many groups specifically for singles looking to meet people, as well as supportive groups for all kinds of kinks and types of kinksters. In the FetLife search field, just type in “[Your City] Kinky Classifieds [or Personals],” “[Your City] Hookups,” “[Your City] Kinksters [or Singles] , etc.
Plura: app for parties, workshops, munches, and other events
ForbiddenTickets: Find both online classes and events and in-person ones around the country
Feeld: dating app for “the open-minded community”
Kinkoo: “helps kinky people find like-minded kinksters”
BDSM.com: More for hookups
Fetish.com: dating and community
Other dating apps or sites, mainly vanilla but you might find kinky people too: Bumble, Hinge, Match, Tinder
Other mainly vanilla social media, but you might find kinky people too: Instagram, Facebook, TikTok