I have a Phalaenopsis orchid that has been blooming on and off for a few years. A few weeks ago a new stem seem to be appearing from a flower stem but now it appear to be leaves and 2 flower buds. Is this the start of a new plant?
Yes, it sounds like you have a baby plant or clone of the mother plant. The Phalaenopsis acts like the common spider plant in this regard. It sends out keiki (the Hawaiian word for baby or child),which, if propagated, can become new flowering plants within 18 to 24 months. If you decide you would like to try to make a new plant, make sure the keiki has a well-developed root system and at least 2 or 3 leaves before you separate it from the mother plant.
Then, pot it up in orchid bark or other appropriate growing medium. You may want to have a look at some specific care websites, as orchids usually produce keiki (babies) when they are under stress. It may be worthwhile to check key factors like light, water and humidity. Here is useful blog: https://www.orchidplantcare.info/
You may also like to review our Gardening Guide — Growing Orchids.