I still don't get how this works. Are there sub-reddit equivalents? Is there an app I can use to subscribe to feeds or topics across multiple Lemmy servers?
Each Lemmy instance (server) has its own communities, which are like subreddits. But instances can read and post in other instances communities seamlessly. For example, there's a gaming@lemmy.ml and a gaming@lemmy.world. They're both separate communities, but you can participate in both regardless of which instance you're a part of.