Take a modular approach to your challenges. Start with a basic map of just some cubes to represent the world. Build your collision system. Once your character manages to stop walking through walls, add buildings it can walk into. Then work on a "trigger" system, as in setting up specific areas where your character can trigger an event, such as NPC interaction. Unfortunately, when I tried to google for rpg tutorials, I found mostly tutorials about the RPG language (which is used on those old as/400 beasts). I'm starting to see your problem finding resources on the matter as a new developer, sorta makes me want to create an RPG now and document the process. So will you be creating this in 3D or 2D? Starting with easier games is a good idea, and simple spaces shooters is always fun to make. Good luck with whatever you end up deciding.