Making a set world.

[fenziie]

So I have been modding the hello-world one off noa-examples, and its been going well, but i just dont have a great idea on how i can create a set world (like just 100x100 simple thing that i can make during game production) and then make it editable by the player (similar to the hello world example where you right click and it creates a block, etc) but the world gen is eliminated and just replaced with that base world I make in production and the stuff the player has built already? Is that possible?