It is in public beta testing phase right now and does lack a variety of features that Discord offers, but you get a lot of basic functionalities to get a head start to start experimenting. If you have used Discord, the user experience will feel familiar. You can explore their project roadmap/release tracker to see what you can expect in its final/future releases.
Revolt is a promising free and open-source choice to replace Discord. Here, we take a look at what it offers along with its initial impressions.