Hi Fiddlegal55,
Thanks for posting your question in Apple Support Communities! We understand you're not seeing the option 'Block Contact' in Mail on Mac. We're happy to help.
It sounds like you're using macOS Mojave 10.14, is that correct? You should see the option to Block Contact, the same as you would based on these directions: Block senders in Mail on Mac.
What type of email account are you using? If you have more than one email account set up in Mail, does this happen with all the accounts, or just one? Is this happening with any and all Sender addresses, or just certain ones?
When you do open Mail > Preferences > Junk Mail, are you saying you do not see 'Enable blocked mail filtering' there, or you can't click the '+' to add a Sender address there?
Your responses will help us isolate this further to determine next best steps to assist.
Best Wishes.