When you first navigate to Reports, you will see the List view of all the reports ever generated. This is where you view and download reports.
To generate a new report click the section you want to see a report for (Customers, Orders, Products Sold, etc.)
This selects the type of report to generate
Select the start and end dates
Click Generate
The system will make a CSV file which you can download from the List view and view using Excel, Google Sheets, etc. Be sure to ENABLE MACROS to be able to experience reports in all their glory.