@Ganesh Sharma , thank you for your question.
Although currently there is no Microsoft document which shares detailed instructions on blue-green deployments to Azure Kubernetes Service through Azure DevOps Pipelines, here is an Azure Sample: Guide to "blue-green" and "canary" deployments using GitHub Actions
Additionally you can check out this blog post: Continuous Kubernetes blue-green deployments on Azure using Nginx, AppGateway or TrafficManager — part 2
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Hope this helps.
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