In addition to what's been said so far, check out !newcomers@piefed.zip (the most recent post was today) or !newtolemmy@lemmy.ca (this used to be the most established community for that purpose, but unfortunately not well-known despite that fact, and with the most recent post being two months ago it seems a little dead lately, though you could try it if you don't get many responses to the former one?).

But that's more for like new to the Threadiverse style of questions. If you instead have questions about a particular app that you use, you'll want to go to the specific app community - e.g. voyagerapp@lemmy.world. And if you have questions regarding the USA, like "how often do Americans take baths, especially in winter time?", then yeah this is the absolute best place for that!:-)