1996 front brakes

The brakes on my cavalier make grinding noise when the pedal is almost to the floor when i stop i just replaced the rotor and the pads

Pull the rear apart and make sure they're not the cause of the noise.

Also, if you mean you replaced the pads/rotors recently, not as an attempt to fix the noise, the fronts could be worn out again. You have to remove the rubber bushing from around the slide pins and remove all the rust and then grease up the bushings on both sides before reinstalling. If you don't do that, the outside pad will never fully release and wear out quickly.