How to Change a Studio Background in Photoshop

Open the portrait and use Select > Subject to create a quick selection of the person.

Refine the edges with Select and Mask, paying attention to hair. Output the result as a layer mask.

Place a studio background PSD below the portrait layer and scale it to fit.

Match lighting by adding a soft shadow on a new layer under the subject and adjusting the background brightness.

Finish with a Color Lookup or Curves adjustment above both layers so the subject and background share the same tone.

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