Hello @Putta, Vikas
Azure Functions provides all the continually-updated infrastructure and resources needed to run your applications. You focus on the pieces of code that matter most to you, and Azure Functions handles the rest.
Microsoft Azure handles all Azure Function related licensing by itself, so you do not need to care about additional cost for your runtime stack in Azure Function.
https://learn.microsoft.com/en-us/azure/azure-functions/
Billing description
https://learn.microsoft.com/en-us/azure/azure-functions/functions-scale#billing