What is the best way to create django app for language learning

I currently want to create an app built on Django. I had some experience with this framework a year ago but I gave up eventually. And now I want to go back to development. And so I decided to create an app for learning 500 most used words in the English language. I've basically made everything look nice and smooth, but I got stuck in the back-end part.

And I seek advice, how to create an interactive app for the flashcard web app. What libraries are used in the most advanced Django apps(I'm okay with reading a lot of material), how to authorize with google accounts, how to collect data from users and know the statistics of the app.

I've read the documentation, watched a lot of tutorials, but they basically teach the low skill stuff and nothing else.

My question is if you were to create an advanced Django app for memorizing 500 frequently used words in the English language, what would you use?. How would you do it?. In what order?