See my blog on check engine light
The scraping and grinding of metal on metal will eventually completely ruin the wheel mechanism. So, as the saying goes, pay me now or pay me later. Brake repair now saves money later on. Any auto parts store can sell you brake pads, but be sure to give them the make and model of your car as the pads may vary from make to make. Back home with your car in the driveway, the next step is to jack it up and remove the wheel.