My ipad pro 22 with m2 chip doesn't show 5G status although the same sim if inserted into iphone 13 pro shows 5G status

The majority of mobile phone SIMs are not correctly provisioned for use with tablet computers. If they work at all, they may not provide access to the full range of cellular services. This is not a limitation of the iPad, but of the Cellular network provider.

If using a physical SIM with iPad, you will require a DataSIM explicitly provisioned for iPad or mobile broadband (a.k.a. MiFi).

Be aware that 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. If you have added a DataSIM and Cellular plan to a WiFi+Cellular model of iPad, the number associated with the SIM card is only used to identify your account for billing purposes. This number is not used for making calls or sending messages.

Notwithstanding that you don’t intend to use SMS/MMS text, your mobile phone SIM may not be correctly provisioned for use with your iPad. You will need to verify suitability of your SIM with your cellular carrier.