To add an AirTag to a second phone, you will need to follow these steps:
Make sure that both phones are signed in to the same iCloud account.
On the second phone, open the "Find My" app.
Tap on the "Devices" tab.
Tap on the "Add a Device" button.
Follow the on-screen instructions to set up the AirTag. This may involve holding the AirTag near the phone or entering a code that is displayed on the AirTag.
Once the AirTag is set up, it will appear in the "Devices" tab of the "Find My" app on both phones.
It's important to note that you can only add an AirTag to a phone if it is signed in to the same iCloud account as the one that the AirTag is associated with. If you want to add an AirTag to a phone that is signed in to a different iCloud account, you will need to transfer the AirTag to the new account first.
