Sometimes it happens because of rotors. If they are old and have a lot of grooves on its surface it will cause the grinding noise. Also it might happen if brakes were not cleaned properly during the replacement.
The brake pads could be worn out
Bleed brakes after changing pads to extract any air bobbles.
New brakes do not grind. If you replaced the brake pads and resurfaced the rotors you may hear a bit of a sound but it is normal until the pads and rotors wear during normal driving.
If your brakes are grinding at all, you need to inspect the brake pads. I suspect you will find your pads are worn out.
No you dont need to bleed the brakes if you are just changing the pads, there are more ansers to car maintenance questions at ; www.carbasics.co.uk
No.
The grinding could be coming from the rear brakes.
check brakes and disc on all four wheels they may be worn.
pad brakes are disc brakes, it's known as changing brake pads for disc setup and changing brake shoes with drum brake setup.
When the pads are under 4 milimeters in thickness.
if when changing brake pads there is air in the system, improperly installed pads, the air in the lines expand increasing pressure on the pad. bleeding the brakes solves this problem.
Incorrect pad / disc combination. There are specific blends of pads that are designed for disc brakes. Some need more metallic components, and some have less. Try the recommended OEM pads for the vehicle.