It's a language learning app. You can learn almost any language you want. It starts you off by testing you what you already know and placing you into the recommended level.
Yep! I agree super good and fun app that helps a lot. I've taken spanish my whole life and it's a good refresher. Have you taken classes for Spanish? Or is this just a thing that you want to pick up? If just picking up, it's kinda of hard because you may be learning the different conjugations and stuff incorrectly or not really understanding it completely. If so, try taking some local community college courses. I wouldn't recommend just going into world and trying to speak with people without at least a basic spanish background. But if you ever want to practice, hit me up! I'm pretty fluent in it. (I'm not hispanic or spanish btw just fyi lol, but I've studied it since forever).
I also use Memrise and Anki. While Duolingo is great it lacks in some areas of learning and responses can be misinterpreted/graded incorrectly.
Sorry for semi-offtopic As said before, there are awesome apps & websites that learn you languages in a not-so-boring way.