Psa 106:34
They did not destroy the nations, concerning whom the LORD commanded them:

Here is the instruction.

Deu. 7:1-7
1 “When the Lord your God brings you into the land where you are entering to possess it, and clears away many nations before you, the Hittites and the Girgashites and the Amorites and the Canaanites and the Perizzites and the Hivites and the Jebusites, seven nations greater and stronger than you,
2 and when the Lord your God delivers them before you and you defeat them, then you shall utterly destroy them. You shall make no covenant with them and show no favor to them.
3 Furthermore, you shall not intermarry with them; you shall not give your daughters to [d]their sons, nor shall you take their daughters for your sons.
4 For they will turn your sons away from following Me to serve other gods; then the anger of the Lord will be kindled against you and He will quickly destroy you.
5 But thus you shall do to them: you shall tear down their altars, and smash their sacred pillars, and hew down their Asherim, and burn their graven images with fire.
6 For you are a holy people to the Lord your God; the Lord your God has chosen you to be a people for His own possession out of all the peoples who are on the face of the earth.

Note:

• the Lord would bring them into the land to possess it
• the Lord would clear the nations before them, nations stronger and mightier
• the Lord would deliver the nations before them
• the Lord would bring victory, they would defeat the nations
• they were to utterly destroy the nations
• they were to make no covenant with them
• they were not to show favor to them.