He was raised in Käpylä, Helsinki, until aged 17, when he moved to United States with his father to play basketball in high school.

During the 2021–22 season, he averaged 8.6 points and 5.6 rebounds as a junior before suffering a season-ending left ankle injury at South Carolina in February 2022.

[9] On 21 February 2024, Michigan head coach Juwan Howard announced that Nkamhoua would miss the remainder of the season after undergoing surgery on his left wrist.

[11] On 3 July 2024, Nkamhoua started his professional career after signing with Niners Chemnitz of the Basketball Bundesliga and the FIBA Champions League.

He was forced to miss the EuroBasket 2022 due to his commitment to Tennessee,[18][19] but next year he represented Finland at the 2023 FIBA World Cup in his first major international tournament.

[20][21][22][23][24][25] He also played in the 2024 FIBA Olympic qualifying tournament,[26] averaging 9.3 points, 3.3 rebounds and 1.7 assists in three games against Bahamas, Poland and Spain.