can hear the rear brakes grinding

Yes. If you are hearing the grinding noise when applying the brakes then more then likely these are either the warning tabs in the pads or they are worn out. Either way, you need to replace them. Here are a couple guides that help with this: This video shows the job being done on a similar car but the process is the same.

https://youtu.be/7a-scFGaYT0

and

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

Below are the instructions from the manual on how to remove and install the rear pads and rotors. Let's run through this material and let me know if you have questions. Thanks