Need Help For a Chat Game

I'm trying to create a game, where player should discuss with a preson (bot with prefixed quotes for each answer) And the app should have a messenger layout. The probleme is that I dont know from to where to start and what should I do?

 

It's a little vague. You should try to think of the "pieces" of your design/code that you'll need and which parts you know/have to figure out.
You could start with scripting learning section, the UI learning section (for example).
It's hard to say what you already know (or don't ) from your question.