The RP hub in general would be Stormwind, if you’re looking for a specific guild for nelves I’d check out this thread it’s got a handful of folks in it that run kaldorei specific guilds.
As for how the community in general works, welcome to Moon Guard! There’s generally a healthy amount of public events you can attend, Stormwind Markets are every monday, Om Nom Noodles has their shop open on wednesdays I believe. If your character is open to cross-faction events the Stonewind Tribe run a storytelling event every saturday around 6 or 7pm server time and there’s Sunday Sermons up at Tyr’s Hand though I’ve forgotten the time for that one. Make sure to pick up elixir of tongues before going to those last two though!