You are sitting on your chair, thinking about you are speaking your favorite language fluently and having much fun. Immediately someone knocks on your door to wrap your dream up! But it is not the end! A dreamer never stops dreaming.
You can achieve this skill undoubtedly as long as you have a passion for it. Let me tell you a story, I was watching Turkish series for almost a year (maybe two days a week) and I never sit in a class or opened any book to learn this language. Besides this, I also chatted with some native Turkish speakers. After that year, I started watching the series without any subtitles, and finally, I could understand 90% of their talks. People keep asking me how I can understand and speak like a Turkish person! You know, all is about passion. When you discovered it, you can speak in any language that you want! It is missed in many sites that want you to learn something!
After that, having a plan, trying the plan (If you could enjoy and learn at the same time), and then it is the turn of consistency! Make it a habit. challenge yourself and follow your heart.