Dear Polina,
I'm so glad you're going to try Lingoleap! It really helped me with my Spanish, so I'll explain how to get started.
To set it up, go to your phone's app store, search for "Lingoleap" and download it. It's free to start with. Open the app and create an account using your email address, then choose the language you want to learn and your level. The app also asks how many minutes you want to practise each day, and I'd suggest fifteen to begin with.
The best features, in my opinion, are the short lessons and the speaking exercises. Each lesson takes about five minutes, so it's easy to fit one in. The speaking practice listens to your pronunciation and tells you what to improve.
My top tip is to practise a little every day, rather than for long periods once a week. Turn on the daily reminder, and try to keep your streak going. It becomes a game!
Best wishes,
Adam