I started hearing a scraping noise when I put my foot on the brakes

Hello,

There are 2 types of braking systems installed at the rear of your vehicle.
The vehicle is either fitted with drum brakes or disc brakes.

Please see images of the various systems below.

At such a low mileage it is unlikely that your rear brakes will be worn out .
It sounds like it could be dirt ingress or some rust which could cause this noise.
I would suggest to first safely jack up your vehicle, remove the rear wheels and inspect the brakes.

Either system requires a different approach to checking, cleaning or replacing .
Below please find instructions how to on both types of systems.

https://www.2carpros.com/articles/how-to-replace-rear-brake-pads-and-rotors

and

https://www.2carpros.com/articles/how-to-replace-rear-brake-shoes-and-drums

Please let us know how you get along .

Cheers, Boris