Generally, you would write the report in some other application, such as Microsoft Word, then save the report to a file and upload the file.
There is a page describing how to submit an assignment athttps://community.canvaslms.com/docs/DOC-9539-421241972
Hello lfields4 Welcome to the Canvas Community. Thanks for posting your question. I would agree with much of what @mzimmerman has posted above. If your instructor is allowing a text submission (How do I submit a text entry assignment?) so that you can type your assignment online and submit it, you can certainly do that. However, what happens if your Internet connection suddenly goes down for an unknown reason? You might lose everything you've typed online. So, being able to type something in a Word document and then attaching it to the assignment submission is a better option in most cases. (See How do I submit an online assignment? and https://community.canvaslms.com/docs/DOC-10663-421254353 for more information.)
I hope this information will be of help to you, Lisa.