If you use Duolingo, maybe don't anymore? The company is moving to be "AI-first" and is using AI to generate their content. Meaning, AI is now generating your language lessons.
They announced that they were going to use AI for this a while back but now they're annoucing that they're getting rid of the contractors reviewing the AI generated content. So, very soon Duolingo is just going to be AI generated slop that might not even be correct.
For alternatives, I'd recommend checking with your local library. For instance, mine offers Rosetta Stone for free if you have a library card.
This applies today and especially when I actually start writing the fic I'm planning