can you send text messages from ipad with cellular?

Unless you also have an iPhone, your iPad cannot send or receive SMS or MMS messages to phone numbers - as these are Cellular Carrier features. Without an iPhone, your iPad is limited to sending/receiving messages via the Apple-proprietary Messages App.

Native iMessages are directed to Apple recipients by their registered email addresses - and not by their Cellular phone numbers. The Cellular number associated with your iPad’s Data-SIM is only used for account identification and billing purposes.

To use SMS/MMS messaging from the iPad Messages App, your iPhone must be logged-in to iCloud with the same AppleID - and message forwarding to your iPad must be enabled on the iPhone.

https://support.apple.com/en-gb/HT208386

I hope this is helpful in clarifying your iPads Messaging features.

Hello,

This feature requires that you also have an iPhone.

How to forward SMS/MMS text messages from your iPhone to your iPad, iPod touch or Mac - Apple Support

By itself you’re ipad is limited to internet message services only since it has no capability to connect to any cellular telephone voice calling system, which is required for SMS and MMS (SMS uses a part of the cellular telephone voice frequency band).

So you can use iMessage between other Apple device users, you can use Skype with other Skype users, Google Hangouts with fellow Hangouts users, WhatsApp web with fellow WhatsApp users, etc.

For SMS or amMS you must have an iPhone to pair with the iPad.