i can not find APN SETTING OPTION

Hi sky rajper,

If you are looking to configure your APN settings as instructed by your carrier or IT dept, you may find the following article helpful:

iOS: About cellular data network settings (viewing or editing the APN) - Apple Support

Note, you may only see this as an option if editing of these settings is allowed by your carrier:

If your carrier allows it, you can view the APN settings on your iOS device in Settings > Cellular >Cellular Data Network.

If you are otherwise having issues with your cellular data connection, you may find this article useful instead:

If you can't connect to a cellular network or cellular data - Apple Support

Regards