Born in Tumaco, Castillo began his football career with local clubs Zipaquirá San Pablo and Expreso Dorado before joining the youth ranks of storied Colombian side Millonarios.
New York Red Bulls II
On 13 April 2021, Castillo left Millonarios, where he had been playing with the team's under-20 side in the Copa Libertadores U-20, to sign with USL Championship side New York Red Bulls II.[1] He made his debut for New York on 14 May 2021, starting in a 1–0 loss to the Miami FC.[2] Castillo re-signed with New York on 27 January 2022.[3]