What is Satan’s partnership with people in their wealth, as mentioned in the Almighty’s saying: “And be a partner with them in their wealth and [their] children”?

Satan's participation in wealth means spending it in disobedience to God or acquiring it unlawfully, such as the forbidden things they used to dedicate to their idols. As for his participation in food and drink, it occurs by not pronouncing the name of Allah (Basmala) when starting to eat or drink, as stated in the Prophet's hadith (definition), where Satan considers lawful the food over which Allah's name has not been mentioned.