'Willy Loman' is protagonist of -

Death of a Salesman, a play in “two acts and a requiem” by Arthur Miller, written in 1948 and produced in 1949.
Miller won a Pulitzer Prize for the work, which he described as “the tragedy of a man who gave his life, or sold it” in pursuit of the American Dream.

After many years on the road as a travelling salesman, Willy Loman realizes he has been a failure as a father and a husband.
His sons, Happy and Biff, are not successful—on his terms (being “well-liked”) or any others. His career fading, Willy escapes into dreamy reminiscences of an idealized past.
In the play’s climactic scene, Biff prepares to leave home, starts arguing with Willy, confesses that he has spent three months in jail, and mocks his father’s belief in “a smile and a shoeshine.” Willy, bitter and broken, his illusions shattered, commits suicide.

Source: Britannica.com