Can you please describe what is a utility short circuit 3-phase and 1-phase MVA? What does it mean physically and how it is generated? Which impedance is used and after how many fault cycles? If I want to generate the utility 3-ph (and 1-ph) SC in ETAP or SKM, what analysis/report should be used?

Thank you for helping a junior engineer!

Not meaning to be glib, but perhaps you should review the power systems text book that you used in your college power systems course.

MVA is just a different format for short circuit current. It is short circuit power which includes the SC current, voltage in KV, divide by 1000 for "Mega" and of course the square root of 3 is in there too. Below is a link to an article of mine from a few years ago that compares various methods, including the MVA method. Hope it helps.

Utility Short Circuit Data - Different Formats