[ moved to the correct forum ]
Use the selection tools of your choice to select the object you want, then select>refine edge or just add a one or two pixel feather, then select>inverse, delete or backspace. If you want a transparent area around your object, before you start, go to the layers panel and double click the background layer to turn it into a regular layer.
Another option is to use the Background Eraser tool. Experiment with its "Tolerance" setting to get a good result. If the subject has areas of wispy hair, for example, using a large diameter brush and the "Discontiguous" limit will "reach in" past the edges of the hair to remove the background that shows through.
As Barbara said, first convert the background to a normal layer, and you can then refine the Background Eraser's result by defringing the layer, etc.
Thanks, I'll give that a try
Sent from my iPhone