Many Gods believed that fate was decided/arranged by the Gods, but in the Odyssey the main source of fate is from Polyphemus’ curse…
“if he is destined to see his friends and his fine house in his own country, may he come there late and in sore distress, in another’s ship, losing all comrades, and let him find great trouble in his home”
this curse comes true:
takes 10 years to get home
loses everything on his journey
all his men die
gets to Ithaca on a boat from the Phaeacians
suitors are exploiting his household trying to marry his wife and kill his son
However there are some aspects where the responsibility relies on others, like the crew may have died to their carelessness instead of the curse e.g. Elpenor