[2][3] Steele and his older brother Jordan spent their childhood practicing baseball in their family backyard.

[4] During his sophomore year at George County High School, while rehabilitating a lower back injury, Steele's fastball velocity increased to 90 mph (140 km/h), which attracted the attention of scouts and recruiters.

[5] He made his professional debut with the Rookie-level AZL Cubs, pitching to a 2.89 ERA with 25 strikeouts in 18+2⁄3 innings during the 2014 season.

The next year, Steele made 10 starts for the Class A Short Season Eugene Emeralds, with whom he went 3–1 with a 2.66 ERA and 38 strikeouts in 40+2⁄3 innings.

[9] He struggled at the start of the season, going 3-5 with a 6.17 ERA in his first nine games for South Bend, and was sent back to Eugene for the month of June.

[11] He started 2017 with the Myrtle Beach Pelicans, but had his season cut short in August due to injury which required Tommy John Surgery.

In 7 starts after the All-Star break, he posted a 0.98 ERA while recording 49 strikeouts before a back injury ended his season.

[25] Steele exited his Opening Day start against the Texas Rangers and was placed on the 15-day injured list on March 30 with a left hamstring strain.