Born on March 12, 1993, in London, England, Vennings began his football career at a young age, playing for local youth teams before being scouted by Brentford FC’s academy. He spent several years in Brentford’s youth setup before making his first-team debut for the club in 2011. Vennings went on to have loan spells at various clubs before eventually signing for Bromley FC in 2017.