there is oil leak from the engine. when im applying break, i heard unnecessary sound like --cruunnkkkk--
Your car has disc brakes and brake pads in the front. The brake pads are like the rubber blocks on a bicycle, If the noise appears to be coming from the front the front of your car the brake pads are probably worn out and may have damaged the brake rotors/discs,If the noise ids coming from the rear the brake shoes may be worn and may damage the brake drums. Get your brakes check as you may have brake failure or do more damage to the brake system.
Oil leaks could be from the valve cover, oil seals within the timing cover, transmission leaks ect....
When your brakes are being inspected ask that the source of the oil leaks be identified. It may require washing down the engine to identify the exact source.