Estimates on the exact distribution of millitary vs Civilian deaths are not known, though millions died in total. That’s just from direct involvement in the war, and not the results of sanctions and embargo or other inflicted terror. I use “hundreds of thousands” because it’s

1. Undeniably correct, even with bourgeois sources alone, and
2. Still gets across the sheer brutality of the US’s genocide on Korea

It’s quite possible that civilian casualties do reach the millions, especially if you include the South Koreans killed by the US and the ROK government in areas like Jeju Island.