Extended maintenance plans cover oil changes and normal scheduled service. They're separate from warranties and only cover some wear parts. Most manufacturers sell one. See: https://www.edmunds.com/car-buying/prepaid-maintenance-plans...

They're sometimes overpriced (due to dealer upsell) and sometimes a good way to estimate what the manufacturer estimates that routine maintenance will cost, at least using their in-house service center. They can run $1000 to several thousand dollars for luxury cars.