Passwords are no longer simple to use or remember. You need a strategy. For example, if you keep a computer in a locked room it is OK to let the computer remember your passwords. If you keep papers in a locked room it is OK to write your passwords down on one. If you keep a list of passwords in a spreadsheet use an encryption tool and don't name the file "passwords."
The best strategy is to use a password manager. A password manager is a subscription service that generates and maintains passwords for you. For example; BitWarden (https://bitwarden.com/) is free for personal use; or Apple's Keychain (https://support.apple.com/en-us/HT204085) stores passwords and can automatically fill in password fields. Learn more about password managers from this article: https://www.popularmechanics.com/technology/security/a26629/use-password-manager/
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