How does Apple avoid receiving text messages about guns in the same city?

Click the settings icon on the main screen of iPhone to enter the settings, scroll down to find "do not disturb mode", and click Open directly.

At this point, the system defaults to "Do Not Disturb Mode" in the off state. Slide the right button to open Do Not Disturb mode.

If you want to completely block this number, just click "Details" in the upper right corner. In the page that opens, click "More" to the right of the strange number. Select "Block this call number" at the bottom of the page. A reminder menu option "You won't receive calls, messages or Facetime from blacklisted contacts" will pop up at the bottom of the page.