Odysseus a hero because he was brave to protect others. For example the poem says "The rest of you loyal friends stay here, while I and my crew take ship and try and find out who these men are whether they are cruel,savage, and lawless, or good to strangers,and in their hearts fear the gods."
Odysseus is also a hero for being brave. For example in the poem "Poseidon, Earth-Shaker, smashed my ship to pieces, wrecking her on the rocks that edge your island, driving her close to the headland so the wind threw her onshore. But I and my men here escaped destruction."
Odyesseus is hero because he had courage to stab the cyclopes in the eye." I ordered the men to cast lots as to which of them should dare to help me raise the stake and twist it into the cyclops' eye when sweet sleep took him.