Hi @XiaofengZhao,

Unfortunately, assignment submission attempts generally cannot be removed from Canvas.  If you submitted the wrong thing the first time, the resubmission should be okay.  Your teacher will see the latest submission by default when they grade.  If they have some kind of policy around multiple submissions, I would suggest sending them a message letting them know what happened.

Your local Canvas administrator (probably in the IT, eLearning, or Digital Education area of your school) may be able to delete the file submitted, but the submission attempt would still be visible.  As a Canvas admin myself, I can tell you that there has only been one instance where I deleted a submitted file, and that's because it was a virus.  Your school may have different policies though, it's hard for us in the community to know what will happen, so just giving you a potential option.

Hope this helps a bit, even if it's not the answer you were hoping for.

-Chris