How should the speed of G code and display interface modify them

Is there a way to change the speed unit from mm / min to mm / S (the speed unit of the display interface and G code is mm / min). What should I do to modify it.

Not sure why you keep opening new threads for the same topic.

As for changing the speed unit, I don't think that is possible. If your GCode contains the feed rates in mm/s you might want to have a look at creating a custom Gcode converter to change the mm/s to mm/min when the file is loaded. See section 2.3:
linuxcnc.org/docs/html/config/ini-config.html