This is what we found on Wikipedia regarding the William Singe:

Liam Anthony "William" Singe (born 2 July 1992) is an Maori YouTuber, singer, songwriter, and record producer. He is most notable for his online videos on YouTube and Facebook.

Singe started his career as a member of The Collective, an Australian boy band which was formed during the fourth season of The X Factor Australia in 2012, finishing in third place. The Collective subsequently signed with Sony Music Australia and released seven singles and a self-titled album. They disbanded after Singe left the group in 2015.

In 2014 and 2015, Singe recorded numerous R&B, pop, reggae, hip-hop and rap covers in his bedroom. In less than a year, he accumulated over two million Facebook fans, reached a number one position on Spotify, 20 million Spotify streams, and earned more than 500 million video views and 2.6 million subscribers on YouTube.