I'm working on a project based on installing a server FTP on Amazon Web Services. I'm doing it through Ubuntu 16.04. No such a matter, everything is doing good so far.
But I got stuck in a step that requires me to type some commands to modify a specific file. I actually typed the commands, but I don't know what to press to save changes and get on the next step. I tried pressing Escape and ControlEnter, but nothing seems to happen. Does anyone have a clue?