Honestly, duolingo is NOT ideal. They don't explain the grammar and yeah, you get it wrong and it's a complete mystery.

My husband who is fluent in Italian and English and took Spanish and understands it fairly well tried to do French on Duolingo and gave up.

I'm doing it because I do know some Italian already and I have taken Spanish in college so a lot of the grammar and conjugation rules I at least understand in principle because they are very close. But I do have moments where I am very WTAF?!