Thanks for asking question! If you are looking for using azure communication chat using Angular and generate tokens in the back-end.
The first thing is to create a communication service resource. After creating Communication service you can look for Connection strings which allow the Communication Services SDKs to connect and authenticate to Azure. You can access your Communication Services connection strings and service endpoints from the Azure portal or programmatically with Azure Resource Manager APIs.
Thanks to Ghanshyam for this article on Azure Communication Chat Using Angular might be helpful
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