Miller played hurling as a student at St Brendan's Community School in Birr.
[1] His performances for the school resulted in his inclusion on the combined Offaly Schools team which won the Leinster PPS SAHC title in 2023.
[4] At inter-county level, Miller first appeared for Offaly as a member of the under-20 team.
[5] Miller joined the Offaly senior hurling team in 2025.
[6] His father, John Miller, played hurling at all levels with Offaly between 1982 and 1995 and was a member of the team that won the All-Ireland SHC title in 1994.