I am still getting to know creo and I would like to have multiple variations of a subassembly which I can switch back and forth in the assembly. I have created different reps in the subassembly. Is there a way to toggle in between the reps in the assembly?
You need to create simplified reps in the using assembly where one of the options is to substitute sub-assembly reps.
Just a word of warning about using simplified reps for product variations, if this is what you mean.
Simplified reps is mostly about assembly (or part) simplification for system performance reasons. You can use it for product variations but that can quickly become unmanageable if you and other users aren't extremely diligent.
I second Stephen's warning against using simp reps for managing product configs/variations. At the last organization I worked at they managed their models in this way and I was the one managing (doing maintenance) on it.
It is very doable when you have a small number of configs, but when you're dealing with hundreds of subassemblies being worked on by dozens of people it can get out of hand. It requires one unfortunate soul to update and maintain all these simplified reps or your designers to always exercise due diligence.