Question
I just inherited an orchid plant I don't know what the name is it didn't have a tag when given to me. The flowers are light pink. The main plant is huge about 2-3 feet in height and 3 feet in width. I need to know when do I transplant this thing.

Answer
That is indeed a large orchid plant.  General advice for orchid plants is to repot when the new growth starts if it is in a pot.  Don't know what you mean by "The main plant".  If there are smaller plants growing on the main plant these could be removed after they have roots formed and be potted separately. It sounds as if you have a dendrobium orchid.  If so, it loves to be pot bound and doesn't care to be repotted.  You didn't mention that the plant is top heavy so I assume it is in a fairly large pot already.  As long as the plant is healthy (and it must be judging by its size), I would keep it as is.