I'm not sure I understand your question, natalia, so I'll just randomly say things and hope one of them is the answer you're looking for.
First of all, the difficulty settings affect nothing but the action sequences, so switching to the easy setting won't remove anything, change the plot, or "dumb down" the rest of the game in any way.
The action sequences themselves are "integral" to the game in various ways, but there's definitely no way around them. Some of them (the ones that occur during dialogues, generally) just add small layers to the story. Others are threats to your mental health, but won't kill you if you fail (unless you lose all your points). The bigger, harder sequences are life and death, though. You fail, you lose. Game over, though usually you're returned to a save point very near the sequence that killed you.
