Follow these steps to learn how to create a duplicate copy of an existing story/backlog item or defect template.
When you copy a template, a new unique ID will be assigned, but the new template will inherit all of the template's details, including associated tasks and tests.
Go to Product > Templates.
Select the template you want to copy, then select Copy from the Generate Story drop-down menu. The new template displays in the grid.
Edit the template as appropriate.