Answer by taking a quote from the following article:

Artis Leon Ivey Jr. (born August 1, 1963), known professionally as Coolio, is an American rapper, actor, chef, and record producer. Coolio achieved mainstream success in the mid-to-late 1990s with his albums It Takes a Thief (1994), Gangsta's Paradise (1995), and My Soul (1997). He is best known for his 1995 Grammy Award-winning hit single "Gangsta's Paradise", as well as other singles "Fantastic Voyage" (1994), "1, 2, 3, 4 (Sumpin' New)" (1996) and "C U

In 1996, Coolio appeared on the Red Hot Organization's compilation CD America is Dying Slowly, alongside Biz Markie, Wu-Tang Clan, and Fat Joe, among many other prominent hip-hop artists. The CD, meant to raise awareness of the AIDS epidemic among African American men, was heralded as "a masterpiece" by The Source magazine. That same year, he recorded the theme song and appeared in the opening sequence of the Nickelodeon TV series Kenan & Kel which ran for four seasons.  After the success of Gangsta's Paradise, Coolio's next album was expected to be another hit. His third solo album titled My Soul, came out in 1997. Although it contained the major hit "C U When U Get There" and the album went platinum, it failed to reach the success of his previous two albums. Coolio was dropped from Tommy Boy Records and his albums since then, 2001's Coolio.com, 2003's El Cool Magnifico, 2006's The Return of the Gangsta, and 2008's Steal Hear, have not charted on any Billboard chart. He did have a minor hit in the UK in 2006 with "Gangsta Walk" (featuring Snoop Dogg), which peaked at #67 on the UK pop chart.  While touring with hip hop duo Insane Clown Posse, Coolio received a tattoo as a homage to the group's fanbase, reading "Jugalo Cool" [sic]. He stated that the misspelling was intentional. Coolio has performed at the Gathering of the Juggalos.  Coolio was featured on an international collaboration track called 'Fuck the DJ' by UK rapper Blacklisted MC also featuring Bizarre of D12, Adil Omar (from Pakistan) and Uzimon (from Bermuda) the song was premiered on music website Noisey from Vice in October 2014.

How was he associated with Red Hot Organization?
Coolio appeared on the Red Hot Organization's compilation CD America is Dying Slowly,