When we dream of an essay, it usually means that we need a kind of feedback in order to help us learn or remember something. We may not be able to change the facts but we can come up with a kind of analysis that is important and meaningful.
Dreaming of an essay is also a sign of anxiety. Dreams are signals that something is bothering you and you need to address it. While it is more common to dream about essays or other academic topics. Some people will dream about completing an assignment, while others may dream about writing that critical paper for class.
It is a sign to put away your distractions, and focus on your priorities before your project deadline approaches.