Buchanan is the son of Stephanie Latiker and has a younger brother, Shunn, who plays for New Mexico State.

[1] As a senior, he scored 23 points in the 6A playoffs to defeat defending champion Murrah High School.

[8] In two seasons at Murray State, Buchanan shot 48.4% from the field, 32.4% from behind the arc and 70.1% from the free throw line.

[12] On February 8, 2020, Buchanan scored a career-high 36 points to go with five assists, four rebounds and two steals in Memphis' 127–119 win over the South Bay Lakers.

[13] On February 29, Buchanan posted a career-high 18 rebounds to go along with 22 points and 6 assists in a 123–120 loss to the Salt Lake City Stars.

[16] In August 2021, Buchanan joined the Grizzlies for the 2021 NBA Summer League[17] and on September 23, he signed with them.

On August 14, 2024, Buchanan signed one–year contract with Šiauliai of the Lithuanian Basketball League (LKL).