Heres some instructions after you are able to get access to the google account. The security questions could be where was your parents born, what's your future job etc if you able to answer two of these questions you'll be given access to the account.
to your locked Samsung phone and provide any random password or pattern for 5 times. After that a message will appear on the screen, tap on “Forgot Pattern”.Then, you will be asked for your Google Account or Backup PIN.
Choose Google Account and go to “Account unlock”.
Enter your Google account password, the mobile will be unlocked.