Hi MT_Spartan,
We understand you'd like to block phone numbers from sending you messages. We're happy to help.
To block a number just open the message, tap the number at the top of the message thread and select Info. Select the Info option again, then select Block this Caller at the bottom of the page. You can do that to each number you'd like to block.
Block phone numbers, contacts, and emails on your iPhone, iPad, or iPod touch
If you've blocked a phone number but messages from that phone number are still coming through, we'd recommend contacting Apple for assistance: Get Support
Hope this helps. Cheers!