I can't text or make calls with my iPhone

Here are a few possibilities:

• Your carrier has a local network outage - call them, and check here: Down Detector - outages
• Your account is not configured correctly by your carrier - Call them
• If you have an iPhone 7, see→iPhone 7 Repair Program for "No Service" Issues - Apple Support
• If your iPhone 7 isn’t covered, or any other model→If your iPhone or iPad shows No Service or Searching - Apple Support
• Your phone has a corrupted baseband firmware:

Go to Settings/General/About and look at Modem Firmware. Is the entry blank? If it is you need to reinstall it by restoring the phone to factory settings, then restoring a backup. Back up the phone first, of course:

1. How to back up your iPhone, iPad, and iPod touch - Apple Support
2. Restore your iPhone, iPad, or iPod to factory settings - Apple Support - follow the instructions to restore using your computer, do not using Settings/General/Reset (which is not included in those instructions)
3. Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

If the modem firmware DOES have a value you may have a hardware problem. The first step is what I just posted, but after that you need to contact Apple support using the Get Support link at the top of this page.

If you are unable make a call or receive; If you can't make or receive calls on your iPhone - Apple Support