For your phone and PC security, it's crucial to resist the temptation of using similar passwords across different accounts. Instead, opt for unique, strong passwords for each account to enhance your security. Additionally, strive to memorize your passwords and PINs so that you don't have to write them down, reducing the risk of unauthorized access to your accounts.
Who writes and fact checks this stuff? Password managers have been a thing for a long time now. It should be considered some kind of malpractice now to ever make a recommendation other than "use an open-source password manager to generate and store randomly generated passwords." That should be followed up with a list of highly regarded options, like Bitwarden and KeePass, both of which are available for virtually every platform.