Ka cika wannan jumla: Miller ya wakilci Kanada a wasanni da yawa na duniya. A watan Yulin 2017, ya fafata a tawagar Kanada da ta lashe lambar zinare a gasar Olympics ta duniya.
FIBA U19 gasar cin kofin duniya. Miller yana da maki 1.6 da 1.7 a kowane wasa. A watan Yunin 2018, ya kasance babban mabuɗin ga ƙungiyar Kanada wanda ya ci lambar azurfa a Gasar FIBA U18 ta Amurka. Miller yana da matsakaicin maki 17.3, 7.3 rebounds, 1.5 taimaka da 1.2 sata a kowane wasa. A wasan kusa da na karshe da suka yi da Puerto Rico, ya zira kwallaye 31 da kuma 14 da aka dawo da su.