I forgot every username and password and I need help step by step. I can't get in my phone, I can't do anything..

If you are talking about the passcode to unlock the phone, read the instructions in the support article that you were reading when you posted your question to the community. This contains all of the help and step by step instructions that you need to unlock the phone.

If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

If you are talking about something else, please explain in more detail.

..... Didn't you post earlier today about this???

Apple would never have contacted you to change your screen unlock passcode. Quite honestly, nobody at Apple will care whether you even use a screen lock passcode or not - that is entirely in your hands. And they certainly do not monitor your screen unlock passcode or contact you about it, ever, for any reason.

Whatever message you received was a scam and it sounds like you gave them your AppleID information. In that case, you will have to call Apple and ask them to help you to regain access and control of your AppleID. Nobody here is going to be able to do anything to help you regain access to a hacked AppleID.

Apple didn't send you that email, it was from a phishing site and they have changed your password on your Apple ID. You need to call AppleCare and ask to be transferred to the Account Security Team.

Apple support contact information is country specific. Click on the contact us link at the bottom of this web page, and change the country icon to the one for your country. If your country is not listed, then Apple does not provide support in your country.