My son has a Iphone 12 The last time it updated it ask for the Apple ID and Password he does not remeber either one

Please check for your son ⤵️

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

If you forgot your Apple ID email address or phone number - Apple Support                  

OR see -> Having trouble signing in?

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

See also -> If you can't connect or sign in to iCloud

If you can't connect or sign in to iCloud - Apple Support

See -> Change your Apple ID password -> Change your Apple ID password - Apple Support

Then see this Apple article: What to do after you change your Apple ID or password

What to do after you change your Apple ID or password - Apple Support

You can help your son, see -> Help a friend or family member as their account recovery contact

Help a friend or family member as their account recovery contact - Apple Support (IN)