Mike wants to know about passwords and how often he should change the ones on his computer. Leo says that local passwords, like for logging into his laptop aren't that big of a deal. Someone would have to have physical access to the computer and a lot of time to crack it. So that's not really the one to worry about. It's the passwords online, and even then, those passwords are encrypted. Those who change passwords a lot are those who have passwords that are shamefully easy to guess. If Mike breaks it up with numbers and capital letters and maybe some punctuation, then it'll be very hard for people to guess it.
Leo also recommends using a password vault. He only has to remember one password, and let the vault generate them and store them all. LastPass is a great option. So is Dashlane, 1Password, and RoboForm. He shouldn't use the same password on multiple sites because if they guess it once, they'll have many others. He should also turn on 2 factor authentication.