This is a tintype photo taken in the 1860-1870s time-frame. Exploring the pre-digital age of photography finds variety in the development of photographs. The tintype was a popular variety since it could be carried with a person, without fear of breakage, while it had a pretty good image. Many of these images are still around today, although some identities are forgotten and some scraps of metal were scratched or bent resulting in damage to the image. This photo is Miss J's Great-great Grandfather Karl Svensson and his brother in law Peter Newberg. These men came across Iowa in a covered wagon with their families to homestead in the Dakota Territory in late 1869.
Choose one of the men to retouch. Crop the photo in half vertically, keeping all of the background you can but cutting out the other gentleman. (You can do both if you want and not crop) The image should remain the same color/tone.
As a retoucher you are bound to keep the integrity of the image for your customer. Don't loose the details in the background components, clothing or identities. Work in a large format when using the cloning tool, or healing tools so when it's reduced to normal viewing size the viewer doesn't see the strokes of touch up or changes. Working with the correct size and intensity of brush will also be a factor in the success of your retouching. Other tools that may work are the blur tool, dodging and burning areas of the image.
This isn't a rush job and will be graded on clarity, tone, contrast, ability, self-challenge and commitment to the task, to have the original image continue on as if it had never been scratched.