This exercise is just about making sure you know how to use Sage. You may be using the Sage Notebook server the online CoCalc service through your web browser. In either event, create a new worksheet. Do some non-trivial computation, maybe a pretty plot or some gruesome numerical computation to an insane precision. Create an interesting list and experiment with it some. Maybe include some nicely formatted text or TeX using the included mini-word-processor of the Sage Notebook (hover until a blue bar appears between cells and then shift-click) or create commentary in cells within CoCalc using the magics %html or %md on a line of their own followed by text in HTML or Markdown syntax (respectively).
Use whatever mechanism your instructor has in place for submitting your work. Or save your worksheet and then trade with a classmate.