want to be和I'm going to be 能互换么？

"want to be" implies that you want to be something or somebody without the assertion that you can BE

" I'm going to be" means that not only you want to be somebody but you also have the resolution to make it.

HOpe this helps

Amituofo

want to be想成为……（只是想，不一定实现）
I'm going to be 我将成为……（已经实施，就快实现，可能性很大）

want to be想成为
I'm going to be 我将成为……（有计划的）