Password management applications are designed to take the pain out of remembering all your passwords. Instead of remembering individual account passwords, you just need to remember the one unique, long, and complex password for your password manager. Your password manager does the rest: generating, saving, and filling in your passwords to all your accounts.
Using a unique, strong password for each of your accounts is the best way to keep your accounts secure. The key to a strong password is length and complexity. Your passwords should be at least 8 characters long and difficult for someone to guess, and not used anywhere else.
Enable multi-factor authentication wherever it is available, especially for the accounts you want to protect the most (e.g. bank, email, etc). In addition to having a strong password, it will help ensure your accounts don't get hacked. It requires both "something you know" (a password) and "something you have" (a phone or hardware fob). After you enter your password, you'll get a prompt or code sent to your device, after you approve the prompt or enter the code you will get into your account.