I don't understand what you mean by "at least 3 options to answer with" - can you explain in more detail, or provide an example use-case? Your command-line-interface might be a single Flash sprite, or ...
Well, the game is about an evil virus that wants to become cute. It communicates with the player through something similar to the old DOS-interface.
What I want is for the "virus" to ask a question i.e. "What do you want to do now?" and the player to be able to answer in at least 3 commands i.e. "Hack"/"Research"/"Wait" which the program recognizes and upon entering the command sends the player to the appropriate next step, be it another question in the "conversation" or another window containing a puzzle-minigame.
I'm not sure what part of this you are having difficulty with. Imagine for a moment that instead of asking for your end user to type something into a text-entry field and to monitor what they type (perhaps when the ENTER key is pressed), that instead you provide 3 buttons on your stage. Responding to a button press in this scenario is much the same as responding to typed user input - your movie does something based on user interaction. Going back to the user entered text scenario, a text or field sprite can detect the ENTER key being pressed and examine the string the user has entered, something like:
on keyDown me if _key.keyCode = 36 then stopEvent sText = sprite(me.spriteNum).member.text case sText of "hack": -- do whatever you need to here "research": "wait": otherwise: end case else pass end if end