Answer by taking a quote from the following article:

Joseph Raymond McCarthy (November 14, 1908 - May 2, 1957) was an American politician who served as U.S. Senator from the state of Wisconsin from 1947 until his death in 1957. Beginning in 1950, McCarthy became the most visible public face of a period in the United States in which Cold War tensions fueled fears of widespread Communist subversion. He is known for alleging that numerous Communists and Soviet spies and sympathizers had infiltrated the United States federal government, universities, film industry, and elsewhere. Ultimately, the smear tactics that he used led him to be censured by the U.S. Senate.

McCarthy was born in 1908 on a farm in the Town of Grand Chute in Outagamie County, Wisconsin, the fifth of seven children. His mother, Bridget (Tierney), was from County Tipperary, Ireland. His father, Timothy McCarthy, was born in the United States of America, the son of an Irish father and a German mother. McCarthy dropped out of junior high school at age 14 to help his parents manage their farm. He entered Little Wolf High School, in Manawa, Wisconsin, when he was 20 and graduated in one year.  He attended Marquette University from 1930 to 1935. McCarthy worked his way through college, studying first electrical engineering for two years, then law, and receiving an LL.B. degree in 1935 from Marquette University Law School in Milwaukee.  McCarthy was admitted to the bar in 1935. While working at a law firm in Shawano, Wisconsin, he launched an unsuccessful campaign for district attorney as a Democrat in 1936. In 1939, McCarthy had better success when he ran for the nonpartisan elected post of 10th District circuit judge. (During his years as an attorney, McCarthy made money on the side by gambling.)  McCarthy became the youngest circuit judge in the state's history by defeating incumbent Edgar V. Werner, who had been a judge for 24 years. In the campaign, McCarthy exaggerated Werner's age of 66, claiming that he was 73, and so allegedly too old and infirm to handle the duties of his office. Writing of Werner in Reds: McCarthyism In Twentieth-Century America, Ted Morgan wrote: "Pompous and condescending, he was disliked by lawyers. He had been reversed often by the Wisconsin Supreme Court, and he was so inefficient that he had piled up a huge backlog of cases."  McCarthy's judicial career attracted some controversy because of the speed with which he dispatched many of his cases as he worked to clear the heavily backlogged docket he had inherited. Wisconsin had strict divorce laws, but when McCarthy heard divorce cases, he expedited them whenever possible, and he made the needs of children involved in contested divorces a priority. When it came to other cases argued before him, McCarthy compensated for his lack of experience as a jurist by demanding and relying heavily upon precise briefs from the contesting attorneys. The Wisconsin Supreme Court reversed a low percentage of the cases he heard, but he was also censured in 1941 for having lost evidence in a price fixing case.

What did he do after high school
He attended Marquette University from 1930 to 1935.