wk3 to csv conversion is probably related to attempts to recover data from very old Lotus 1-2-3 spreadsheets and save it to CSV format that can be transferred to another software, typically Excel. While some earlier versions of Excel were actually able to support direct import of Lotus 1-2-3 format, this is probably no longer the case in the modern versions. And same goes for Open Office/Libre Office and similar productivity suites.
The easiest way how to achieve this is perhaps by finding Lotus 1-2-3 on some of the abandonware websites and use that to export the data. Tools for Linux like gnumeric might also still support Lotus 1-2-3 formats, but unless you have access to a computer with Linux, you would have to run it as a virtual machine.
Updated: August 15, 2023