I clicked on the Norton 360 icon. At the top of the screen I clicked on Settings. On the next screen that came up I clicked on AntiSpam. I went into Norton Anti-Spam and set up an email definition in the blocked list.
Norton AntiSpam does not work if your SMTP or POP3 email port is an SSL-encrypted email port. Your Norton product supports all email programs that use non-SSL POP3 and SMTP communication protocols.
No one can block spam from getting into your account. The only thing you can do is manage it after it gets there.
Are you using web based email or a local client? If a local client, you can set up filters in your email client. That is what the Norton Anti Spam filters do for you. Here is a Norton Support article to help you set it up. https://support.norton.com/sp/en/us/home/current/solutions/v1083859