i went to an auto salvage for rims but all of their cars are lifted off the ground. how can i get the nuts off when the wheel turns with the tire iron?

No. 1-1

let them help you, or bring a battery powered impact gun to take them off. Most junk yards have tools for that if you're buying stuff like that. Here in houston most have mexican dudes working in the yards to do it for you as long as you're a paying customer.