How do I get the calendar to sync with my syllabus?
I am not sure I understand what you are asking.
When a graded activity (quiz, assignment or discussion) is created in Canvas, an entry is automatically created in the Course Calendar, and in the Course Summary area of the Syllabus page. And when any graded activity is revised, Canvas automatically reflects those revisions in those two areas. There is nothing to "sync".
Learn more in the following chapters of the Instructor Guide: Calendar, Course Summary.
If I have missed the mark, please explain further and I will try to help.
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