Please your question in more detail. We can't have any idea how to help you with such a terse post.
Here's what you do: warp stabilize png
The source of your track matte goes above the layer you want to apply a mask to. Press F4 until you see the track matte column in the timeline. If you are using a JPEG as a track matte you must select Luma or Inverse Luma on the layer below your track matte.
Simple as that. Otherwise, we need details about exactly what you are trying to do and with what.