People often ask me how to become a filmmaker. I tell them: Just start making films.
Grab a smartphone & begin. Don't worry if the films are good. Your first films will be bad no matter how much thinking & planning you do. So just begin right now. Make the mistakes, learn the lessons, & make more films.
As you go along, you find your voice. And, one day, you make something that's pretty good. And it leads you to the next thing, which is even better.
That's how you become a filmmaker. In fact, it's pretty much how you become anything.