Hi Arthur,
I'm not sure what you want.
To display current clients date time in this format you may use the string function to convert or a display format for a today() computed field in a datawindow.
e.g. String(today(), "m/d/yyyy h:mm am/pm")
If you use a datawindow with computed field you may keep the field automatically updated if you set the "Timer Interval" property of the datawindow. It specifies the number of milliseconds after the timer updates the computed fields. It is 0 by default.
HTH,
René