Try this: Enhanced Input in UE5 | Tutorial
It notes:
Backwards Compatible with the old system
Enhanced Input is completely backwards compatible with the old Input “Action and Axis” mappings. Just change the DefaultPlayerInputClass and the DefaultInputComponentClass to be something based on UEnhancedPlayerInput and UEnhancedInputComponent respectively.
I too was taken aback but this looks a lot more refined/central and can be mapped across various controllers vs having to implement a dead-zone mechanic, and the like. Going forward, once I flip over, I don’t see the need to go back (myself).