I want to become a film director. I feel that I have great vision, a minds eye, so to speak. I am constantly imagining things and angles and all that stuff. I watch documentaries and behind the scenes stuff more than film themselves! I am passionate about film.

I do have a problem though. Im not a dialogue writer. I can write scenes, story flow, character backgrounds, but story and dialogue are not my strong suits. How can I get started with that handicap in mind?

Hire a writer.

If you want to become a director, start planning to go to school and look for an apprenticeship/understudy position you can do.

Most directors are not writers.
The director is hired to direct the movie making process/vision, or they pick a script they like that someone else wrote, or the director collaborates with writers to make the script.

Not everyone is Tarantino

But taking classes on how to write a screenplay would be a good start.