Try "which" followed by the name of some of the more common ones (emacs, vi, vim, nano, pico), one at a time to keep the returned strings simple. I find this method safer than just arbitrarily entering a command (the name of one) and finding out I can't exit it without terminating the shell session (or worse).

Whichever one comes up with a path to an executable, like /usr/bin/emacs2 instead of a lot of garbage telling you where editor x isn't in your execution or environment paths, that's the one you have.

And you may have more than one. Try them out and see which one you're more attuned to.

BZT