Miller was born and raised in the Algiers neighborhood (15th Ward) of New Orleans, where he was exposed to jazz culture and history. He is the great-great grandnephew of Papa John Joseph, a New Orleans bass player who worked with Buddy Bolden. Joseph died during a performance of "When the Saints Go Marching In" with the Preservation Hall Jazz Band. Miller sang at home and church from an early age. Although initially drawn to the
drumset, Miller began to study the trombone around age ten or eleven, inspired by his middle school band director Keith Hart. He progressed quickly and impressed professional trombonist Terrance Taplin, who encouraged
Delfeayo Marsalis to audition Miller for his Uptown Jazz Orchestra. After sitting-in with the group at New Orleans' famed jazz club
Snug Harbor, Miller joined the group at age 14. He studied academics at
Benjamin Franklin High School and music at
New Orleans Center for Creative Arts. While a
sophomore in high school, he performed with the
Preservation Hall Jazz Band at
Carnegie Hall. During high school, he appeared for three seasons of the
HBO series
Treme, in which he played a student of Antoine Batiste, the fictional trombonist depicted by
Wendell Pierce. In 2013, Miller was selected as one of twelve younger musicians to participate in the Vail Jazz Workshop in
Vail, Colorado. The experience solidified his desire to pursue music as a lifelong calling. In 2014, Miller was chosen to be in the 2014 GRAMMY Band, a program that selected high school students from across the United States to perform during GRAMMY Week. ==Musical career==