Please follow the steps for the category wise report

Login on Back Office > from the left menu click on ‘Reports’  > click on ‘Sales’ tab  > select shop from ‘Select Store’ drop-down > from the next drop down of ‘Select report type’ click on ‘Summary’ > now select ‘CATEGORY’ option from the drop-down list of ‘Sub Report Type’. As the last step please select the appropriate date range from ‘From To Date’ & click on ‘Apply’ and click on the ‘Submit’ button to view the report.