I'm annoyed at my so for not wanting to try scary films
Why are you mad that he doesn't want to watch scary movies?
That is what I am studying and I want to share it with him.
I'm sorry that you are feeling annoyed. It's bad to get too upset at your partner over something minor. You should respect his wishes and just watch those kinds of movies on your own.
Why I don't get what he is doing it wrong?
We all have different tastes, and maybe he just doesn't enjoy horror films. There is nothing wrong with that.