A bad actor can discover your name, location, online accounts, contacts, and even your Social Security Number if your email address is part of a severe breach. They can use this information to launch phishing attacks, spam you, steal your identity, or compromise your security. Check haveibeenpwned.com to see if your email was leaked. All you need to do is type in an email address. Check your personal email accounts as well as those of your family members.
This site also shows the largest breaches and the most current reported breaches.