I remember reading Walter Mitty when I was in the 7th grade. It was in my literature textbook and I don't think there's a fictional character that I can relate to more than Walter Mitty.
I can't recall it perfectly but it's basically about a meek old man living a completely ordinary and anonymous life spends his days having vivid daydreams of being various things. A master surgeon saving someone's life, badass soldier, spy, etc.