In Genesis, Noah was a farmer after the Flood when he planted a vineyard. Genesis 9:20 describes Noah as “a man of the soil” and says that he planted a vineyard after God’s covenant with him and his descendants.
The story then says that Noah drank wine from the vineyard and became drunk, lying uncovered inside his tent. This episode is separate from the Flood itself and belongs to the narrative about Noah’s life after leaving the Ark. It also introduces the actions of his sons Shem, Ham, and Japheth.
Translations vary slightly in wording. Some say “man of the soil,” while others use “farmer” or a similar phrase. The underlying occupation is therefore agricultural, and the vineyard detail explains why farming is the clearest concise answer.
A common mix-up is to describe Noah as a shepherd because livestock were aboard the Ark. Genesis does not give him that occupation. It specifically connects his post-Flood work with cultivating land and planting a vineyard.