How do you change emails

i was given a zte android phone that someone forgot the email and password so how do you reset that? i already factory reset but that didn't remove email on file for devise

crwdns2893858:0crwdne2893858:0 crwdns2893862:0crwdne2893862:0

crwdns2894050:0crwdne2894050:0

crwdns2889612:0crwdne2889612:0 0
crwdns2892346:0crwdne2892346:0