I am trying to submit an essay but when I click on the assignment tab nothing is coming up on the page.
Are you getting a completely blank page, or are you just not seeing any place to submit the assignment?
I would check with your instructor, to be sure that the assignment is set up to allow for online submissions. When creating assignments in Canvas, if the instructor does not specify that it is an online assignment, Canvas treats it as something that must be submitted in person.
There is a page with instructions for submitting online assignments that shows what you should be seeing at How do I submit an online assignment?
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