How does a student submit and assignment to Dropbox from a computer? The assignment is currently saved on my computer in my documents.
If by "Dropbox" you mean how do you submit to a Canvas assignment, then it is quite easy.
You can learn more at How do I submit an online assignment?
I hope this is helpful,
If you mean "Dropbox" as in the third-party cloud storage solution, you could create a shareable link to a folder in your Dropbox, then paste that link in Canvas on a content page, announcement, instructions to an assignment, etc. If you're having them submit online, you might try out using the built-in submission functionality of Canvas that Kelley L. Meeusen is describing.
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