What am I missing???
I don't know if I'm missing something or not, but I just started Duolingo a few days ago, and if I hadn't been raised by parents who spoke Hungarian to me, I could not follow along with these lessons. I do not understand how a non-Hungarian speaker is supposed to learn like this. What am I missing? I do the practices and take the quizzes. Where is the lesson? Where is the part where you learn the vocabulary words and meanings? Even having heard Hungarian all my life, I'm still having problems with the accent marks and vocabulary.
Read the introduction to each skill; then for new words, hover over them. If they really are new words (not just ones you forgot) it may be useful to jot them down in a notebook.
Also many discussions teach useful grammar points (I usually check out the discussion on a each question - sometimes there is nothing useful but sometimes there is gold there too).
In the web version (not in the mobile app), when you click on a skill (i.e., one of the round icons), there will be a "lightbulb" symbol. If you click on that lightbulb, you will see the "Tips and Notes" for that skill.
Edit: I wrote "key" instead of "lightbulb". It's the light, not the key! ;-)
It's partially learning by trial and experimentation. If you hover/tap the dotted underlined words you will see the use/translation for that word. That in conjunction with the tips and notes (easier to find on duome.eu) is how one learns on Duolingo.
That being said, it is not complete or an equivalent of text book learning. Many of us supplement with texts books (Halló, itt Magyarország, or Colloquial Hungarian) as well as courses on Memrise. It's by no means perfect, but I have not found a better online resource for learning Hungarian.
You are also fortunate to have heard Hungarian at home, so you already have a leg up on the rest of us. Not all Hungarians spoke Hungarian around their children.
The essence of Duolingo is the gamification. That's why it is not like the traditional learning methods but that is why many people love it. The Hungarian course contains about 1200 words and some grammar, that's enough for a beginner.
But if you want to develop your Hungarian further, read interesting Hungarian books, listen to the radio or watch TV and learn some grammar. Considering you want to learn Hungarian, you're a lucky guy because your parents speak Hungarian to you.