can one send text messages from an non-cellular iPad without owning an iPhone??

An iPad, whether a Cellular model or not, is not capable of directly accessing Cellular Voice or SMS/MMS Messaging features. An iPad with either WiFi or Cellular connectivity alone can only access IP-data services.

However, If paired with an iPhone, the capabilities of iPad significantly broaden to include access to Cellular Voice and Messaging services of the associated iPhone - relayed to the iPad over WiFi using Apple’s continuity features. In absence of an iPhone, iPad can still use the Messages App to send and receive iMessage between Apple devices.

For your interest, more information about Continuity and the relevant Cellular services can be found here:

Continuity

Use Continuity to connect your Mac, iPhone, iPad, iPod touch and Apple Watch – Apple Support

SMS/MMS Messaging

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

WiFi Calling

Make a call with Wi-Fi Calling – Apple Support

“Messages” is a term generally used to describe SMS Text (Short Messages Service) and MMS Picture (MultiMedia Message) messaging. SMS/MMS are messaging services associated with - and exclusively carried over - Cellular (mobile phone) networks.

”iMessages” are Apple’s proprietary messaging services that work between Apple devices. iMessage supports many types of content beyond that of simple text or photos. iMessages are always sent over IP-Data.

IP (Internet Protocol) Data is carried over modern Data networks, such as your broadband internet connection. Modern 3G, 4G and 5G Cellular networks carry IP Data in addition to their traditional Cellular Voice and SMS/MMS messaging services (these are legacy services from older second generation Cellular services).

Apple’s Messages App can combine Cellular (SMS/MMS) messaging services and Apple’s iMessage service in a single App.

When using the Messages App, the App will automatically determine which messaging platform (Cellular or iMessage) to use in sending a message to the recipient. Where the recipient can receive an iMessage, the App will send the message using IP-Data; if the recipient cannot receive an iMessage, the App will instead send a message using SMS/MMS. It follows that an SMS/MMS message can only be sent over a Cellular connection (if available).

The Apple Messages App indicates which service is being used. When sending iMessages, the message “bubble” is shown in BLUE; when sending SMS the message “bubble” is GREEN.

I hope this simplified description and clarification proves to be helpful to you.

Not sms messages

Just text messages from the Messages app.

Sorry.