I'm not going with my parents to buy furniture
That's understandable, is there a specific reason why?
I think that my parents are wrong in doing so, I don't even like the color of the furniture.
Your parents are completely capable of furniture shopping by themselves, don't feel obligated to do things you don't want to do.  They will understand if you would rather not go, especially if doing so makes you uncomfortable in any way.
No way, I hate my parents so much.
Although you might not enjoy being around your parents, you should never say you hate your parents.  Everyone has been upset with their parents at some point, but just keep in mind they are just trying to help you succeed in life.