!lemmy_support@lemmy.ml seems overall pretty technical, but I've seen people post asking about how to use the site in general. There might be other communities as well.

lemmy@lemmy.ml is probably your best bet since I think that's the community about Lemmy on the instance run by the Lemmy devs. lemmy_support@lemmy.ml is another option but might be more about running an instance, though I'm not positive.

The "chat" community on most instances is another good rec, especially on the midsized ones. Like people ask Lemmy how-to or recommendation questions all the time. Neat as I can tell they're mostly a catch all for conversations, so questions get asked a lot too.

All the major lemmy instances usually have a community dedicated to answering questions about lemmy. I'd suggest you to check out https://lemmy.world/c/support since your home instance is lemmy.world