Many websites require a username and password to keep your personal data secure, however, if you use an unsecure password this can make you vulnerable online. The first step to keep your passwords safe is to choose passwords that are difficult to guess and unique for every website. The more complex your passwords are the better, for example, using a random combination of upper and lower case letters, numbers and special characters is best practice.
If you are concerned about remembering all your passwords we would recommend using a password manager (like the ESET Password Manager) to store and secure them. That way you only need to remember one password. In addition, remember to never share your passwords with anyone.