Operation between two fields

I want to make a comparison between two fields, I’m needing to check if is less or equal and show a message if is less or equal at the API

This is the method post to enter the values to compare, and in the model this fields are the type integerfield, and the values are deudasTotales and PagoDeuda

Is there a specific question you have about this? Is there some part of this you need assistance with?