Completely locked out of phone

See this Apple article: If you forgot your iPhone passcode

https://support.apple.com/en-us/HT204306

Have you forgotten your Apple ID?, check your Apple ID via your email box, see this Apple article: If you forgot your Apple ID

https://support.apple.com/en-us/HT201354                  

OR see -> Having trouble signing in?

https://iforgot.apple.com/password/verify/appleid

Have you forgotten your password? -> See this Apple article: If you forgot your Apple ID password

https://support.apple.com/en-us/HT201487

Again:

See this Apple article: If you forgot your iPhone passcode

https://support.apple.com/en-us/HT204306

Have you forgotten your Apple ID?, check your Apple ID via your email box, see this Apple article: If you forgot your Apple ID

https://support.apple.com/en-us/HT201354                  

OR see -> Having trouble signing in?

https://iforgot.apple.com/password/verify/appleid

Have you forgotten your password? -> See this Apple article: If you forgot your Apple ID password

https://support.apple.com/en-us/HT201487

First, erase it with a computer. If you forgot your iPhone passcode - Apple Support

Then, use iforgot.apple.com to reset the password.

He forgot the email?

In that case, you should work with the email provider to see if you can recover the email to proceed.

Is it an iCloud email by any chance?