My phone is not Receiving service, and I got a message That says An update is required to use cellular data on this iPhone

Try first to optimize the range of the mobile network, see this Apple article:

If you see No Service or Searching on your iPhone or iPad

If you see No Service or Searching on your iPhone or iPad - Apple Support

See the following Apple articles:

If you see an Update Failed or Apple Pay Not Available alert after iOS update or restart

If you see an Update Failed or Apple Pay Not Available alert after iOS update or restart - Apple Support

Manually update your carrier settings on your iPhone or iPad

Manually update your carrier settings on your iPhone or iPad - Apple Support