Wait, M-ME?!
Ok, well uh, first, before you make an RPG, you should write out like a plot. This is the one I did for a coder king mystery:
Then, the format that you code it up in should should relate to the game you’re making. The story extension is good to use, like @soren_lorenson said. Though, I prefer to use the Fancy Text extension, and make your own frame, add a few animations, transfer it into a function, then the dialogue should be more polished!
Again, here’s the one I put in for The Coder King Mystery.
That’s just for dialogue though. The actual gameplay is your choice 
I hope I was less useless than usual 