And to add to Kyatrics turn-based movement tutorial, have a read here:
Random dungeon generation
With a random dungeon and turn based movement, you have the basics of a roguelike game, then you only need to add the mechanics like: combat, gear, loot, story, ...
I would advice to start with something more simple to get used to C2. Easiest way to master C2 is learning by doing. Start with a "Pong" Remake, do a endless scroll shooter, make a jump'n'run. With the skills you got by programming these easier types of games, you will have less problems setting up a game like this.