Some film cameras would let you do double exposures.
Digital cameras will not let you do that.
Using an enlarger with film, you could also superimpose one photo onto another.
An enlarger for digital cameras is a software package called Photoshop by Adobe.
You can do just about anything your imagination wants with digital manipulation with Photoshop.
Photoshop is very powerful and it takes a long time to be proficient with the software.
But there are hundreds of tutorials that explain how to do "whatever" with Photoshop.
Here are some:
http://tinyurl.com/yaoeoxj
..
.
I knew a film photographer that would take a picture of something like a landscape, then over the same frame take a picture of a person. There must be a way to do this with digital editing. I can paste a picture in another picture, but it isn't the same. Any suggestions for improving picture on picture?

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