what was the first catch and what does the old man plan to do out of kindness?

The old man's first catch was a tuna.

“The bird is a great help,” the old man said. Just then the stern line came taut under his foot, where he had kept a loop of the line, and he dropped his oars and felt tile weight of the small tuna’s shivering pull as he held the line firm and commenced to haul it in.