I have a group shot. I need to add a person which I can do. I need to move him behind someone.

Hi John.  I am thinking that the best approach here would be for you to share the full res originals and describe the edit you wish to make.  Someone will quickly do the job (because they are unable to help themselves) and describe the process with a series of screenshots.

A lot depends on the original group shot of course.  This is a random shot I found with Google.  Moving any combination of the back row to create a space to insert another person is going to lead to holes that will be tricky to mend.

Separating the two men and moving them around, is still going to leave holes

So the trick will be to make a plane that leaves you with the least number, and smallest of holes to fix

Please share a screenshot of your document with the Layers panel visible, so we can better assist you. To make the person appear behind someone else, you will need to create a mask on the person layer and mask the parts that should be hidden.

You can learn more about masks and how to use them in Photoshop here Use masks to hide layers in Photoshop (adobe.com)

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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