When you are using a language actively, like listening, reading or talking French, you are using your language intuition - a superfast language processor built into your brain. This part of your mind is made for interpreting a language superfast, so you in real-time can understand what is being said, and produce sentences yourself in that language.

To learn facts about a language - like memorizing grammar rules - does not help you much in your practical use of the language.

So how do I then learn French the fastest?

Reading large amounts of French texts, listening to it spoken, watching movies, and so on.