Can ford ranger rims fit on a dodge caravan?

No, Ford Ranger rims are almost certainly not going to fit a Dodge Caravan. While both are vehicles, they have different wheel bolt patterns (the number and spacing of the lug nuts), different wheel diameters, and likely different center bore sizes (the hole in the center of the rim that fits over the hub). These dimensions need to perfectly match for a wheel to fit safely and securely. Trying to force incompatible wheels onto a vehicle is dangerous and can lead to wheel failure.