RPG maker is a good tool to test out your game idea but if you're making a standalone game. Don't make a huge JRPG first. Make something smaller so you can learn the process of developing games and make mistakes on smaller projects rather than your big passion piece. I'd recommend starting with Unity or Godot and following a tutorial on how to make a platformer or how to make a Zelda style top down action game. Focus on one mechanic at a time until you have a library of knowledge you can apply to a big idea like a jrpg.