How can I draw an edgeworth box with 3 different goods? If there are 3 types of goods(x,y,z) and 2 consumers (a,b) how can I draw the Edgeworth box? It must be 3 dimensional, right?

Is there a software or online tool that I can use to draw a 3D Edgeworth box?
I assume what you're asking based on your comments is: "How can I visualize indifference curves for 3 goods?" I can think of three options:

1) Use a tool like Matlab, or its open-source equivalent, Octave, to plot 3 dimensional indifference curves. Here is a tutorial on how to do that.

2) Make a series of 2-dimensional indifference curves for two of the goods, and fix a different level of the third good for each one, that is, plot a series of cross-sections of the 3 dimensional box.

3) Using paper and pencil, draw a general $n$ dimensional Edgeworth box, then, set $n = 3$.