You just write out the dream -- most writers put dreams and thoughts in italics to show that they're not actually part of the action.
It depends on what sort of story you're writing. It maybe be helpful to but a dream sequence in italics, just as you might place a character's thoughts in italics. If you're able to convey clearly that what you are writing is a dream, italics are not needed, but again, italics may be a helpful choice for the reader if you go directly into the dream sequence.
It can be staged that way. Adrian Noble's production, known for a lot of upturned umbrellas, and which was committed to film in around 1994, was notable for treating the whole story as a dream. In the film version Osheen Jones represented a boy who is dreaming the story.
Only if your main character is a protagonist, which is the hero in the story/novel.
Point of View means which character is speaking or thinking. You write an account by writing what that character would have seen/heard/felt during the story.
a story about writing a story (apex)
This seems to be a wish-fulfillment dream. Your own mind creates a happy story for you to enjoy in the security of sleep. However, it does not predict the future and it does not mean the girl is thinking or dreaming of you.
a story with footnotes that comment on the author's process
No one. There's nothing about King Arthur dreaming, or even falling asleep in the story.
It depends on what story you're writing!You can have a character of any age you want, so pick one who would fit your story best.
No. The game is not a dream. The character actually signs up for a job at the pizzeria. Now, however, FNAF 4 is a dream, but that's a long story.
The main character/s tell/s the story.
It depends on what you want to happen. It's your story. Are you looking for a way to break an unbreakable chain? That's not going to happen if you made it unbreakable, so you'd better go back and make it breakable instead.