Lots of questions. I see some answered already(I would like to know the paywall thing myself). If you are trying to talk to your groups of friends privately. there is https://nostrapps.com/0xchat

You also may want to check out these two app/tools indexing sites and browse around all of the different nostr apps and see if something stands out for you. https://nostr.net & https://nostrapps.com/

It's a bit confusing/overwhelming out there since there is so much development going on! Hopefully it isn't information overload.