The son of Hall of Fame player Shaquille O'Neal, he attended Crossroads School in Santa Monica, California.

As a senior forward, O'Neal was ranked among the top high school basketball players of his class.

[1] His interest in basketball grew after he had a disappointing performance at a middle school Amateur Athletic Union game and was prompted to "prove everybody wrong" on the court.

[1] Starting in his freshman season, O'Neal played basketball for Windward School in Los Angeles at the forward position.

[11] On June 29, 2016, the Los Angeles Times announced that O'Neal would transfer to Crossroads School in Santa Monica.

[12][13] He joined the team expected to take a leading role with top high school recruit Ira Lee.

[20] Sources: During practices over the summer, O'Neal began dealing with health issues, and was given a heart monitor by doctors to wear.

[22] In April 2019, UCLA hired Mick Cronin as their head coach to replace the fired Steve Alford.

[23] O'Neal made his UCLA debut in the 2019–20 season opener, playing six minutes without scoring against Long Beach State.

[23] On February 14, 2020, O'Neal announced that he was transferring to Louisiana State University, where his father played college basketball.