you can change the message in login screen by using login_errors filter hook, just paste this code in the themes functions.php file :
add_filter('login_errors','login_error_message');
function login_error_message($error){
//check if that's the error you are looking for
$pos = strpos($error, 'incorrect');
if (is_int($pos)) {
//its the right error so you can overwrite it
$error = "Wrong information";
}
return $error;
}
for registration screen error refer this codex page
https://codex.wordpress.org/Plugin_API/Filter_Reference/registration_errors