I think that it's too big project and there are hundrets of project like this, so you can download them and than add stuff that you want, there is no need to writing "core" again, because you have it really glitchy, you can jump to block if you are holding forward key, you still see through block ..
I understand you that you want to make something like Minecraft, i also like this kind of game. But doin't "core" mechanic is quite hard to do right. It may work now for you but then when you would like to add more chunks you will realize that you don't have optimalized code and you need to rewritte it from ground.
So i would recomend to find some working core system (blocks) and then you can and your custom crafting, monsters, etc...