@Yash For Http request - response please follow : https://learn.microsoft.com/en-us/azure/connectors/connectors-native-reqres
For implementing the logic, you can use Condition Control to check the operator provided in the request body and use Math Functions for compute purpose. Then you can pass the output ( ref to : https://learn.microsoft.com/en-us/azure/logic-apps/logic-apps-create-variables-store-values) in the Response action
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