welcome to Q&A
if i understood correctly, You need to setup authenticator on 2 different IOS/Android device and same should active on both the devices.
Option 1- You can simple Backup Autnetcator app on Icloud and same you can restore to another IOS device. (Not sure about ANdriod)
Option 2 -
Manually Add Accounts
Log in to Each Account:
Go to the security settings of each account you use with Microsoft Authenticator.
Add to Secondary Device:
Choose the option to set up a new authenticator app.
Scan the QR code with Microsoft Authenticator on your secondary phone.
This will add your account to the new phone.
Repeat for All Accounts:
Do this for each account you have in the Authenticator app.
Please accept as answer if it helps