These links/sites might be helpful for email and site security:

MX Tool Box

All of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool.  Input a domain name or IP Address or Host Name. Links in the results will guide you to other relevant tools and information.  And you’ll have a chronological history of your results.

 

Have I Been PWNED?

Check if your email or phone is in a data breach