When the Lord your God brings you into the land you are entering to possess and drives out before you many nationsthe Hittites, Girgashites, Amorites, Canaanites, Perizzites, Hivites and Jebusites, seven nations larger and stronger than you 2 and when the Lord your God has delivered them over to you and you have defeated them, then you must destroy them totally.[a] Make no treaty with them, and show them no mercy. 3 Do not intermarry with them. Do not give your daughters to their sons or take their daughters for your sons, 4 for they will turn your children away from following me to serve other gods, and the Lords anger will burn against you and will quickly destroy you. 5 This is what you are to do to them: Break down their altars, smash their sacred stones, cut down their Asherah poles[b] and burn their idols in the fire. 6 For you are a people holy to the Lord your God. The Lord your God has chosen you out of all the peoples on the face of the earth to be his people, his treasured possession.
What part of that sounds like it's about race instead of religion?
In those verses? A lot of it, honestly. It uses religious context as motivation, but the verses mention not sparing people groups as much as it mentions destroying religious artifacts. Hell, the final verses further support this by reinforcing the idea that they were the Lord's "people," a group that he himself has chosen out of all other groups of people. I don't think "race" and "religion" were quite as separate back then as we might consider them to be now, especially not to the ancient Hebrews.