1) How to monitor azure functions, how they are running/status/errors ?
You can use Applications Insights:
Monitor executions in Azure Functions
https://learn.microsoft.com/en-us/azure/azure-functions/functions-monitoring
2) How to troubleshoot functions ?
You can use the diagnostics tool within Azure Functions:
Azure Functions diagnostics overview
https://learn.microsoft.com/en-us/azure/azure-functions/functions-diagnostics
3) How to know to know, how much time functions are running and which time will trigger(schedule time).
Timer trigger for Azure Functions
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