How do I return from the dialogue below into my plain writing once again? Do I begin a new paragraph? The old man is impressed by Manolin's catches, and he congratulates him. Promptly following, Manolin proclaims that the old man and him can fish together again, the two soon conversing of their next voyage's preparation. Manolin states: Now we fish together again. No. I am not lucky. I am not lucky anymore. The hell with luck... I'll bring the luck with me. What will your family say? I do not care. I caught two yesterday. But we will fish together now for I still have much to learn. We must get a good killing lance and always have it on board... It should be sharp and not tempered so it will break. My knife broke. I'll get another knife and have the spring ground. How many days of heavy [rain] have we? Maybe three. Maybe more. I will have everything in order (125).

Every line of your dialogue should include quotation marks that begin and end each exchange. For example, the first two lines of your conversation should read as:
"Now we fish together again."
"No. I am not lucky. I am not lucky anymore."
And so on. That way, when you return to the narrative in a new paragraph, the reader will understand the difference between when the characters speak and when the essayist returns.
Is this entire block a quotation from The Old Man and the Sea? If so, make sure to copy it exactly as Ernest Hemingway wrote it, or exactly as it appears in the source you are using. If there are cues like "the boy said," you must (or at least should) include them. Those cues must appear outside the quotation marks, though. For example, I believe the full text reads:

"The hell with luck," the boy said. "I'll bring the luck with me."

These character cues allow the reader to follow the dialogue more easily. I see you took this one out and inserted an ellipsis in its place. I wouldn't do this. You want to make your essay as logical and as easy to understand as possible.