Amos says he was not a prophet by profession or a prophet’s son. He describes himself as a herdsman and a dresser of sycamore figs, and says the LORD took him and sent him to prophesy to Israel. See Amos 7:14–15.
In Amos 7:14–15, Amos answers Amaziah’s challenge by explaining that he did not come from the usual prophetic pipeline. He says he was not a prophet by trade, nor raised in a prophet’s household, but worked as a herdsman and a caretaker of sycamore fig trees. These verses sit in a confrontation scene within Amos’s vision section (Amos 7–9). Just before this, Amaziah, a priest connected to the royal sanctuary at Bethel, reports Amos to the king and tells Amos to leave and earn his “bread” elsewhere (7:10–13).
Amos presents his authority as coming from a direct call from Yahweh, not from a recognized religious career path. In his own words, he was not a “prophet” as a settled role and not a “prophet’s son,” but a rural worker (herding and sycamore-fig work).
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Amos 7:14-15, then read the surrounding section so the answer stays connected to the passage's flow.
14Then answered Amos, and said to Amaziah, I was no prophet, neither was I a prophet`s son; but I was a herdsman, and a dresser of sycamore-trees:
15and Yahweh took me from following the flock, and Yahweh said to me, Go, prophesy to my people Israel.