I kind of grew up with English, it started early on, and went on throughout education. Still, a subsequent period of translating and reading creative texts (literature, songwriters' lyrics) made the leap, making me really comfortable "in" the language and its culture, and enjoy its beauties.
To get fluent in a new language, I'd recommend spending time together among native speakers wherever you can meet them, ideally in the country of the language. Coursebooks I think need to be assisted with some first-hand immersion into the culture. and nothing can possibly beat having a native girl-/boyfriend alongside the coursebook in making you a fluent speaker in a way shorter time than you would imagine. that's how my German got fluent as it is now.
To get fluent in a new language, I'd recommend spending time together among native speakers wherever you can meet them, ideally in the country of the language. Coursebooks I think need to be assisted with some first-hand immersion into the culture. and nothing can possibly beat having a native girl-/boyfriend alongside the coursebook in making you a fluent speaker in a way shorter time than you would imagine. that's how my German got fluent as it is now.