She's just trying to 'earn a living'. [=to earn the money needed for food, clothing, etc.]
He will do anything to 'earn his keep'. [=to earn what is needed to support himself]
He 'earned/won his spurs' by doubling the company's profits in the past year.
(..) l only tell you for your own good. Cooped up here. Suffocate in summer, freeze to death in winter. Breathing fumes. And you earn chicken feed. Don't you like anything about it? Oh, it grows on you. Sometimes you listen... and the house is full of people... (..)1988 Cinema Paradiso