Hi there!
I'm native in Spanish and have been learning French for the last 10 years and I think what it really makes the difference in order to become fluent is to immerse yourself in the target language culture. Before, my French level was just average, but as soon as I started studying in France and learning about their culture, films, books and lifestyle I did find that my level was radically boosted in only a few months. Plus, there is no need to live in a French-speaking country, there are many other methods to become fluent in one language, have a look! : https://blog.lingolistic.com/best-way-to-learn-french