What do you mean by a lot? There are millions of neurons in a human's brain.
The number of neurons in each person varies due to generic differences so it is impossible to tell how many mirror neurons one has. If you are asking this question because you have witnessed a two year old behavior and observed that they copy a lot of actions, then I would say that it is a learning process that kids go through. They touch matters and try to identify substances and get used to their textures.