When your brakes are squeaking you can go to an auto parts store or Walmart and buy some brake cleaner that you spray on the brake rotors which help clean them off to prevent the squeaking.
You just spray the brake cleaner on the brake rotors and it evaporates and cleans the rotors.
Then also spray some Gunk brake quiet brake squeak cure on the brake rotors too and it will help prevent the brakes from squeaking.
But if your brakes are squeaking because they need replaced then the spray won't fix the problem and you'll need to replace the brakes.
So make sure the brake pads and rotors are in good condition because bad brake pads and brake rotors can cause squealing of brakes.