Is it possible for photographers to teach themselves to direct?

A "director" is not like a tailor or a doctor. Because the director himself doesn't have any "professional skills"

You teach yourself. You have nowhere to start? Yes, because it is not professional, there is no standard to judge right or wrong.

To put it bluntly, the director just organizes a group of people to understand what is in the director's mind.

In fact, it depends on two things:

First of all, you have your own ideas (you must know what you want)

Second, you will lead others (there are photographers, actors, and even art lighting, and you should convey the specific things in your mind to them)

So "self-study" is certainly feasible, because no one needs to teach.

According to your situation, I suggest you learn editing, because for "movies", "montage" is a means of telling stories.

And photography is just "telling the truth"