I'm not sure what you mean by "onions". Do you want to grow onions?
Are you asking about finding seeds to grow Phalaenopsis? If so, do you have a laboratory or access to one in order to germinate the seed? Orchid seed is done most efficiently under sterile laboratory conditions. Some people do it out of their home, but are generally experienced growers. It might be easier to get seedling Phals or flasks (if you are an experienced grower) and grow those.