My prof wants us to upload files, not attach and then upload them.
Summer, that's an interesting question. In my mind uploading files to Canvas and attaching files are the same thing. In a round about way I could see uploading and then attaching a file in Canvas (you could upload it to your Personal Files and then attach it to your assignment). Yet, I'm not sure how to attach and the upload a file. My recommendation is to contact your Instructor and ask for clarification on what exactly they are looking for.
Sorry I can't be more help!
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