Hello @amfabs
You're receiving spam, which is endemic across all of the Internet.
Because it's impossible for ISPs and security vendors to stop this at source, the best thing to do is to set up filters or mail rules at your end, usually in your email client program (such as Outlook or Thunderbird), to filter out such messages and either delete them or place in a separate folder which you can then check at your leisure.
You may also be able to filter spam and other unwanted messages through your security software.
If you can provide the name and version of the email application you use, we can provide links to help guides on setting up such rules.
O.