layers Panel

Another option-

1) Open ONE  image (background layer)

2) Go- Menu: File > Place Embedded

3) Choose the image for the second layer.  (it creates a Smart Object layer)

Another Option would be using 

File > Scripts > Load Files into Stack 

Hi Bill.  Has Jane answered your question?   Are wanting to compose the two images in the same document? 

Can you explain in more detail what you are trying to achieve, or perhaps show us an example of something similar?

In the example below there are two women on different layers, but we can only see the upper layer because it covers the layer beneath it.

We need to make room for both layers by expanding the Canvas (Ctrl Alt C or Cmd Opt C)

I've doubled the width of the cavas, and moved the two layers so that both woman can be seen

You mentioned masking, and that has become incredibly easy and accurate in recent versions of Photoshop.

Select one of the layers and the Select Object tool, and click on Select Subject in the Options Bar Note: your toolbar will not look like mine but you can find the Object Selection tool by holding down the shift key, and toggling through with the W key.

With the selection in place click on the Add Layer mask icon at the bottom of the Layers panel.  The background will be hidden.

Do the same with the other layer.  Add a new layer at the botttom of the layer stack, and fill with a colour, or use File > Place Embedded to bring in a new background image

Does that get you started?  Where do you want to go from there, (if that's whe you wanted to be)?

@William5DDA 

The two images need to be in the same document and not in two separate documents. Try this:

• Window > Arrange > Tile to put both documents side-by-side
• Move tool > Drag one image into the other window. Hold the Shif key to center it. Both are layers in the same file now.
• Close the one document
• Create a layer mask (Layers panel) on the upper layer

Show a screen shot if you need more help.

Jane