I have an executable of a (rather simple) GUI application on Linux, built in Qt5. I am able to run it, and want to find out what happens internally when I press one of the buttons. I suspect that the button might not just execute some code but run another executable, which has been packaged into the main one. I want to find out which code is being run, or extract the executable (if my assumption is true), both would be fine. I know roughly what function name to look for, since I can sort of guess it from what the button does and it's tooltip.
The ultimate goal is to isolate the functionality of the button to be able to run it on the terminal.
I am new to reverse engineering, please excuse if anything I write is wrong or trivial. So far I have found this and this question which are kind of related and use
readelf, but so far I had no luck with those.