What is the old man's native town? What is his occupation?

The short story "The Old Man at the Bridge" by Ernest Hemingway takes place in the Ebro Valley in Spain during the Spanish Civil War. The narrator, whose mission is to scout for enemy troops, encounters a tired old man near a pontoon bridge over the Ebro River and strikes up a conversation with him.
The old man informs the narrator that his native town is San Carlos. He has just come from there. He was the last to leave because he was taking care of animals: a cat, two goats, and four pairs of pigeons. The narrator urges the old man to go up the road and get on a truck bound for Barcelona, where he would be safe. However, the old man is too tired to move, and besides, he is very concerned about the animals he has left behind. By the end of the story, it is unclear whether the old man will be able to get out of the way of danger before the enemy troops arrive.
As for the old man's occupation, it is not stated in the story. The narrator says that he does not look like a shepherd or a herdsman. The few animals he mentions are probably just personal pets. The old man gives his age as seventy-six, so it's possible he has no occupation. He is most likely too old to work and simply takes care of himself and his animals. He says he has no family, so the animals are the only living things he has to be concerned about.

The old man's hometown is a place called San Carlos. He was forced to leave there on the orders of a captain, who told him to go on account of an artillery bombardment. The town was simply no longer safe for any civilian. The old man was reluctant to go—he was the last one to leave town—not least because of all the animals he was caring for.
We never find out exactly what the old man's occupation was back in San Carlos. Maybe he didn't have one. He is seventy-six years old, after all. The soldier narrator observes that the old man certainly doesn't look like a shepherd or a herdsman. This indicates that looking after all those animals was a labor of love for the old man; he did it because he enjoyed caring for animals. And as he had no family of his own to care for, those animals were pretty much his whole life. That explains why he remains slumped down wearily at the side of the dusty road, despite the imminent arrival of enemy forces. Without his animals, the old man's life is effectively over, and he cannot, and will not, go any further.