It's recommended to change the oil every 10,000 to 15,000 miles, depending on your driving conditions. Brakes typically need attention around 30,000 to 50,000 miles, but inspect them regularly.
If you start hearing squeaks or feel any weird vibrations when braking, don’t wait, get them checked ASAP. And for oil, I’d say don’t push it too far past 10k miles if you want the engine to stay happy!