You can follow these steps to make changes to existing questions in your report template.
Navigate to the Templates page.
Click on the Edit template icon next to the template containing the question you want to edit.
You should now be able to see the Edit Template page. Click the row for the question you want to edit in the Questions section.
Make your edits and click Save to save your changes to the question.
Note that if you change a question name or type, you may introduce errors into any rules that use that question. Be sure to test your template after editing a question.