Hi

If you can't remember your id the page that you posted from has instructions for how to find it : If you forgot your Apple ID

If you've forgotten the answers to your account's security questions : If you forgot the answers to your Apple ID security questions

Or its password : http ://iforgot.apple.com

You should be able to recover your ID email if you've already read the information here: If you forgot your Apple ID

If you can't remember that Apple ID passcode, then see this article: If you forgot your Apple ID password - Apple Support

EDIT: And King_Penguin beat me to it. 😉

Contact Apple support here ...

https://support.apple.com/en-gb/HT201220

Head over to https://iforgot.apple.com to get started with recovering your account information.