Archange joined the Chelsea Academy at the age of 10 and played in both midfield and defensive positions while progressing through the ranks at the club. He has travelled and been a part of various overseas tournaments with the academy, including the 2010 Dallas Cup.

In the 2010-11 Archange started being picked for reserve team matches, and scored his first goal away at Manchester United in April 2011. Another high point for Nkumu was that he started in the second leg of the 2011-12 FA Youth Cup final, which Chelsea went on and won

On 23rd August 2012, Nkumu joined League One side Yeovil Town on a one month loan spell. Nkumu made his professional debut on 18th September 2012 in a 4-1 loss against Leyton Orient as a late substitute. On 23rd October 2012, Nkumu signed on loan for Colchester United until 14 January. He made just one appearance for both Yeovil and Colchester

Released by Chelsea early in 2013, he joined Spanish side Granada on trial in March 2013.

On 15th April 2013, he played on trial for Norwich's Under-21 development squad in a game against Bolton which the Canaries won 1-0. He then played in the 3-1 defeat against Manchester City's Under-21 development squad on 26th April 2013.

He trialled for Leicester's Under-21s in August 2013, playing in a defeat to Sunderland on 19th August.

He joined Concord Rangers but moved to Hendon in February 2014. He was released at the end of the 2013/14 season.

In 2015 he moved to Iceland to join KA,making 69 appearances in four seasons and helping them to promotion in his second season. After a short spell back in the UK with Haringey Borough, he joined Throttur Reykjavik in April 2019.