Oil changes
Oil and filter, on the schedule your vehicle actually needs.
Coolant service
Flushed and refilled before old coolant stops protecting the engine.
Brake fluid service
Flushed so the pedal stays firm and the lines stay clean inside.
Transmission fluid service
Changed on schedule to keep shifts smooth.
Filter replacement
Air, fuel and cabin filters, checked at every service.
Scheduled maintenance
The full list for your mileage, done in one visit.
Not sure which of these you need?
Describe the vehicle and what is bothering you about it. That is usually enough to work out the rest.