See If you forgot your Apple ID password https://support.apple.com/en-us/HT201487
You also can use Having trouble signing in/iForgot https://iforgot.apple.com/password/verify/appleid
And you undoubtedly will need to see If you forgot the answers to your Apple ID security questions https://support.apple.com/en-us/HT201485
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If you end up not being unable answer your security questions successfully, and I think that is very likely, then see: Security and your Apple ID https://support.apple.com/en-us/HT201303
This document says “without proof of your identity via security questions and other carefully selected criteria, Apple Support can't help you reset a password or perform any other actions on your account.”
Thus, we can do nothing to help you if you can't answer your security questions successfully, except to mention that Apple support might help you if you have an extenuating circumstance (e.g., you have the receipt for your purchase of the device new with its serial number on it). If you want to contact Apple support to discuss any possible extenuating circumstance, see these support options:
Get a call from Apple support to help solve your problem using this
link https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362
Apple ID Support https://support.apple.com/apple-id
Apple ID account security for country-specific and region-specific help https://support.apple.com/en-us/HT204169
Get Support: We’re here to help https://getsupport.apple.com/. Go through the options to find the best support option.