Bike brakes squeaking noise removal

I was suprised when I tried to ride my bike this morning, there was this problem in my brakes that it produces so much noise that i feel that it lessens its ability to brake hard. I was sure I was careful with my brakes and it was not broken or something the last time I used it. Well anyway, the problem is here all we need is a solution.

Step 1. Get a clean dry cloth (be sure you will not be using this for any other purposes other than on your bicycle) and any kind of degreaser.

Step 2. Clean the disc/rotor with the cloth.

Step 3. Apply the degreaser to the disc/rotor until whole disc/rotor is wet enough. Apply also some degreaser on areas near the brake pad(the one that compresses when the brakes are squezzed). You dont have to disassemble it but just apply until where you are able to reach.

Step 4. Wait for degreaser to take effect for about 2 mins. Then try rolling your bicycle wheels then braking very softly, and repeat it until you cant hear a thing.

Step 5. Dry up the rotor completely by using the cloths mentioned earlier.

Done! Try repeating STEP 3 if it still sounds. Thank you!