why my disk shows 2 can't delete it ??????????

As @Barney-15E has mentioned, that is all perfectly normal for macOS 10.15+.

See these Apple articles for changes to the drive layout which began with macOS 10.15+:

About the read-only system volume in macOS Catalina or later - Apple Support

Signed system volume security in iOS, iPadOS, and macOS - Apple Support

Unfortunately the Apple article does not show everything in the new drive layout. Here is a third party article with some details, but keep in mind Apple has been slightly modifying the layout with each major OS release since Catalina (10.15) so there may be some other slight differences to a Ventura layout. Apple Silicon Macs introduced even more changes, but Disk Utility won't show anything outside of the main APFS Container.

https://eclecticlight.co/2020/09/16/boot-volume-layout/

You don't have two disks.

You are seeing a header for the Volumes.

You see the subdued System Volume. If you expand that you will see the mounted sealed snapshot of the System Volume.

Below that is your Data volume.

They are all on the same single disk, and there are several more volumes on that disk.

I tried to explain that it is how it is supposed to be. You can’t delete it and you shouldn’t delete it.