You can build an application, create a docker image and upload it to AWS ECR using Azure DevOps build pipeline. Later deploy this image from AWS ECR to AWS ECS Fargate container using the Release pipeline in Azure DevOps.
You can use deployment job in pipeline to deploy your microservice in Kubernetes resource created in environment.
How to fix issues related to Helm chart deployment to Kubernetes
For an Azure RBAC enabled cluster, a ServiceAccount gets created in the chosen namespace along with RoleBinding object, so that the created ServiceAccount can do actions only on the chosen namespace.