If you wish to start the Windows Fax and Scan program, which allows you to fax or scan documents via a fax machine or scanner attached to a system running the Microsoft Windows operating system, from a command-line interface (CLI), you can do so by opening a command prompt window or a PowerShell window and typing the command
wfs
and then hitting Enter.
There are a few command line parameters you can enter when staring the
program from the command line. E.g., you can enter
wfs /swtich fax
to start the program with its faxing interface;
wfs /switch scan
is the alternative for starting with the
scanning option. Without those, the application will start in the last used
mode. For other possible arguments to the app, see
Windows Fax And Scan Command Line Options?