FORGOT ICLOUD ID

Have you tried : If you forgot your Apple ID - Apple Support ?

To then reset its password : If you forgot your Apple ID password - Apple Support

Or, and if the problem is activation lock and if you were the original purchaser of the phone (i.e. it’s not second-hand), you could try going to an Apple Store (make a Genius Bar appointment if you do) or try contacting iTunes Support online (https://www.apple.com/emea/support/itunes/contact.html) and see if they can remove the phone from the account - they are likely to want to see proof of ownership before they might help e.g. original receipt with the serial number on it

(For future info typing all in capitals is considered shouting, makes posts difficult to read, and may mean that people are less likely to reply.)