What's problem you are encountering?
I am unable to put text on a 3D cube.
I am able to have six words to choose from which is the answer to a sentence with one missing word.
I want the six choices to be on a rotating 3D cube.
No. I develop educational apps for kids. This app would teach 700 of the most used words in English for Reading and Spelling. I could also teach math facts with choices on a 3D cube.
There's no library for writing text onto a 3D plane - never mind then animating them , so all of that would need to be created in the first place.
Which would be a fair bit of work
All things are possible, but I feel that getting a smooth looking animation rate is probably not going to be easily achievable
And I'm assuming that is the main idea behind this project - to have a nice looking cube that people can use a mouse to rotate it and then click on a face to accept the written text as the answer?
This probably won't help with your Snap! project, but if you want to create educational apps it would be easier to do it with an existing framework like Three.js.
The WRITE block will write at an angle, so you could use that for an approximation to what you want, but it doesn't change the size of the letters to match perspective lines. Maybe you could use that as a first approximation while researching true 3D text.
Umm you position the sprite where you want the text to be, facing the direction you want the text to go, and then you find the WRITE block, down near the bottom of the Pen palette. Do you have a more specific question?