What is a website everyone should know about?
https://lemm.ee/post/1008147
What is a website everyone should know about? - lemm.ee
haveibeenpwned.com
To figure out if your email addresses are part of a known breach. Also, start using a password manager (bitwarden.com)

Have I Been Pwned: Check if your email address has been exposed in a data breach
Have I Been Pwned allows you to check whether your email address has been exposed in a data breach.
Have I Been Pwned