To identify which report to use, navigate to Reports > Builder for the Template Select screen.
Use the Filters in the left side Menu, and also the settings at the top right of the Template screen to reduce the options and help you to choose the correct template.
Reports that are already being used in the Workspace Report Bundles are flagged as IN BUNDLES hover your mouse on the flag and it will reveal which Bundles the report template has been used in.
The Eye symbol on each template allows you to review the columns in the report, and help you to quickly choose the right one, before having to set the criteria and build the report from your data.
Dynamic Templates option gives you the ability to build your own templates as required and keep your own library of reports.