Easy ! If there is no FileVault or Firmware password , and assuming that the late owner had a somewhat recent version of MacOs installed.. then you would boot up from the Recovery Partition and reset the main/admin/login password thru that: read on.. to get to the recovery partition, restart the MacBook, on startup, hold down the Apple + R keys on the keyboard together.. if you see a ianguage selection screen.. it worked.. pick a language & continue.. move the cursor( the arrow) to the top center of the screen and click. You should now see OS X Tools. From there, pick Terminal. Click on it to get it going. You should see a white screen with black letters, numbers and characters. This is OK and normal.. from there, type in
“resetpassword” ... but without the quote marks( “”) .. press Enter/Return on your keyboard. This gets you into the main/login/admin/startup password reset app.. that should do it..
if it has a firmware/file vault password.. you would have to phone call/ make an appointment at your local Genius Bar ( apple store) or see your local aasp( apple authorized service provider with proof of ownership of some kind) and they’ll be happy to take care of that for you.
good luck
john b
