@Roshan kumar
Thank you for your post!
When it comes to importing a certificate(s) to the Azure Key Vault, you should be able to reference our Import a certificate in Azure Key Vault tutorial, which will walk you through the whole process from beginning to end.
Additional Links:
Set and retrieve a certificate from Azure Key Vault using the Azure portal
About Azure Key Vault certificates
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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