You need to have a solid benchmark of how long it takes your program to ciomplete.
You may have 2 or 3 commands, but you need to know how long each takes. If the 2nd one takes an hour and the last one takes 2 minutes, that is information that must be know ahead of thime.
Next you need to know how long each piece takes and what you can use for a measurement. For instance, if you have an input file thqat has 100,000 records every 10,000 records woule be 10%, You may need to get the rcords count of the complete file and then have a counter in the program to know when you hit a milestone to adjust your progress bar.
SO I believe the simple answer is “It Depends”. You have to do your homework first and thne use that information to determine you progrress.
Hope that helps