I am trying to keep hackers from stealing my information. I have websites that need protection from hackers off my sites.I got an email from United State Financ

I am trying to keep hackers from stealing my information. I have websites that need protection from hackers off my sites.I got an email from United State Financial office telling me that someone is stealing my money from my sites.If it is any way possible i can stop that from happening please let me know.I have antivirus.Thank You!!