why not create , probably the word I am looking for
is a game engine, that can create a program that will simulate a world similar to earth but easily
edited with really generalized tools to shape areas
You're talking about a tool for creating game worlds with. That's off-topic in the Game Design forum,
so I'm moving it elsewhere. (Level designers might conceivably use this tool you envision, but it would
not be a game designer or level designer who would create the tool.)