Ngoo began his career as a youth player for Southend United. In July 2009, he spent time on trial at Manchester United representing them in the Milk Cup at under-16 level, with United winning the tournament. He had attended Brampton manor school based in East Ham.
In September 2009, aged 16, he signed for Liverpool for a fee that could reach up to £250,000. During the 2010–11 season whilst representing the club's under-18 side he scored 15 goals in 21 appearances. The following season he was the reserve team's top scorer.
On 14 September 2012, having scored the under-21's final goal in a 4–1 over Chelsea Ngoo revealed a T-shirt bearing the message "96 reasons 4 Justice". Ngoo was booked for the tribute which came in the week that the Hillsborough Independent Panel released their report. In January 2013, he was loaned to Heart of Midlothian to gain first team experience.
At the end of 2013–14 season, he was released by the club.
Having been watched by the club in several of Liverpool's under-21 games on 24 January 2013, it was announced he was set to join Scottish Premier League side Heart of Midlothian (Hearts) on loan until the end of the season, subject to the paperwork being completed. The deal was completed the following day, meaning he teamed up with fellow Liverpool player Danny Wilson who was also on loan at Hearts. Ngoo was given the squad number 21. The following day he made his debut against Inverness in the Scottish League Cup Semi-final, scoring Hearts equalising goal. Hearts won the match 5–4 on Penalties, after a 1–1 draw, with Ngoo also scoring one of the penalties. On 17 March 2013, he was ultimately a losing finalist as Hearts were beaten 3–2 in the Final against St Mirren. Ngoo picked up a shoulder injury which he struggled with towards the end of the season and forced him to miss their 3–0 win game over St Mirren on 4 May. In all he played 17 times during his spell in Scotland, scoring five goals. Ngoo commented that he believed he had improved as a player during his time with the Edinburgh side.
On 10 July 2013, Ngoo signed with newly promoted Championship side Yeovil Town on loan for the 2013–14 season. On 3 August 2013, Ngoo made his Yeovil debut as a half-time substitute in their 1–0 win over Millwall. He made his full debut for Yeovil on 6 August 2013 in a first round League Cup tie at Southend United, he played 82 minutes before being substituted for Kieffer Moore in a 1–0 victory for the Glovers. He made two substitute appearances before his next start at home to Birmingham City and away at Burnley, both matches Yeovil lost. He started Yeovil's next home league game against Derby County, but only lasted 45 minutes in a 3–0 defeat after he was substituted for Andy Williams at half-time. He was again dropped to the substitutes bench on his final two appearances for the club, twice substituted in on both occasions, playing six minutes against Reading and 11 minutes against Queens Park Rangers.
On 9 October 2013, Ngoo returned to the Liverpool after his loan spell was ended by mutual agreement.
On 31 January 2014, Ngoo joined Walsall on loan. On 8 February 2014, Ngoo made his debut against Milton Keynes Dons, he went on to miss a penalty in a 3–0 defeat. On 18 April 2014, Ngoo scored his first goal for the club, with an equalising header in a League One match against Carlisle United in a 1–1 draw.
On 15 August 2014, Ngoo joined Kilmarnock on a two-year deal.
Following his release from Kilmarnock, Ngoo began training with National League side Bromley. The club announced his signing on 19 November 2016 and he made his debut the same day by coming off the bench against Chester in the 78th minute.
On 20 January 2017, Ngoo signed for League One side Oldham Athletic on a short term contract until the end of the season. Ngoo was released by Oldham at the end of the 2016–17 season.
In September 2017 he signed for Albanian side Tirana on a one-year contract, with the possibility of a renewal for a second year.
Ngoo represented England at under-19 level. He was called up to the England squad for the U-20 World Cup in Colombia in 2011, making his debut on 1 August 2011, coming on as an 72nd-minute substitute in a group match against Argentina, replacing Callum McManaman in a 0–0 draw. In all he made three appearances at the tournament. He is also eligible to represent Nigeria through his mother, and Cameroon through his grandfather.As of 18 May 2017
Heart of Midlothian
Scottish League Cup runner-up (1): 2012–2013
Albanian Supercup: (1) 2017