[bluGill]

I did about a year of Duolingo. I didn't learn the language, but I learned enough that I had a chance. It is hard to learn a language, and Duolingo is a good first step: it gives you a good grasp of the most common words/grammar - enough that you can jump into something that is fun (that is you can understand enough content to do something other than focused study).

There are better ways to learn a language, but there is no method that has every possible language you might want to learn. DuoLingo is a tool in the toolbox, use it and move on. Very few tools will actually go from 0 to fluency in a language.