Did you do the steps like in this documentation: https://docs.mendix.com/howto/integration/importing-excel-documents#1-introduction

And also take a look at these modules: https://appstore.home.mendix.com/link/app/72/Mendix/Excel-importer

And this one: https://appstore.home.mendix.com/link/app/726/Mendix/Excel-exporter

Or even this one: https://appstore.home.mendix.com/link/app/109927/Daywize/TemplaterForMendix

Regards,

Ronald