Let’s take a look at the renderings and original pictures first:

renderings 
Original picture Pull off the legs
and copy one layer

make a picture frame


Adjust it with layer styles
![Photoshop makes mm's legs stick out of the frame]()
Finally, a few slight modifications were made and it was done.

This example just provides a method,
As for making a beautiful picture frame, you can check out other tutorials. The key is to make it look like it came out of a painting.