My father programmed in COBOL, but he never talked me about this. Anyone mind to share his experience? What would be to do this today? is it hard to learn?
I don't know that anyone would ever want to do things the same way today. Today we expect interfaces to adjust to the available screen and font size, which to the best of my recollection was not something that the old COBOL screens could do. There are still 'text-based user interface' tools available, although the modern approach is to link them into the program as a library rather than having them built into the language runtime. The curses (or ncurses) and s-lang libraries are what comes to mind.
The second rule of COBOL programming is...