Hi, Brenna!
You are certainly welcome to add a photo to your essay; however, please be aware that it will not impact your grade. You will be graded on your writing alone.
Also, please be aware that we may need to remove the photo in order to upload the essay back to your page; sometimes, depending upon the photo size, the addition of a photo will cause the file size to be too large for upload.
Please let me know if you have any other questions!