Hello ST2212 and welcome to PSG.
I agree with Tom that this image was created in camera.
There are many ways to accomplish this type of effect, here is one.
If you have an image like this one..........(not me in the picture)
Duplicate the image twice (2) and turn off the original.
On the first duplicate, right click the layer and select 'Convert to smart object'.
Then add a Gaussian Blur. Since we converted the layer to a smart object, we can go back and adjust the blur if needed.
On the second duplicate layer, add a layer mask.
With the selection process of your choosing, mask out the subject that you don't want to be blurred.
Here's what the mask looks like.....
And this is how your final image will appear.
