I know, i am boring, repeating same stuff forever.
But some advice, for all those great RPG or whatever big game idea ppl. :
First do tiny game, so you can see how much work is required for making even smallest game.
And by doing game i mean whole game, together with options, audio, working gui.
Then polishing it, fixing bugs testing. So whole road up to release ready game.
I am repeating this over and over, not to be sarcastic or “i told you so!”,
I am doing to to save You from losing potentially months or years.
Just do that tiny game first to have idea what it will take to do your real thing later.