Can’t connect to internet after I leave my home

First, try a forced restart. If that doesn't work, do you see a message up at the top of your screen that says No Service or Searching?

• Press and quickly release the volume up button

• Press and quickly release the volume down button

• Press and hold the side button.

• When the Apple logo appears, release the button.

https://support.apple.com/en-in/guide/iphone/iph8903c3ee6/ios

JAllport wrote:

How come See above

Contact your cellular data provider.