Q: Ipad won't accept my apple ID to Icloud

The iPad is on the activation screen ? If it is, and if you can't remember the id that you were using in Settings > iCloud on it, then have you tried : If you forgot your Apple ID - Apple Support ? You should be able to confirm if it's the correct account by seeing if the iPad shows on the Find iPhone section of the account in http://www.icloud.com

If you still can't find it, and if you were the original purchaser of the iPad (i.e. it wasn’t bought used), 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 iPad 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.