Zhi Xing Liu (CSI Interfusion Inc) Thanks for posting your question in Microsoft Q&A. To deploy an APIM instance and APIs via ARM, you would need to generate ARM templates. Refer sample templates available in azure-quickstart-templates/quickstarts/microsoft.apimanagement/ repo which covers a lot of different scenarios including all sub-resources such as APIs, policies, users etc.
Alternatively, if you have existing APIM instances with APIs, policies, you can use extractor tool available in azure-api-management-devops-resource-kit repo to generate ARM templates or creator tool to create API templates based on Open API specification.
Once you generate ARM templates, you can automate the deployments using GitHub actions, CLI, PowerShell and Continuous Integration and Continuous Deployment using Azure DevOps will provide the detailed steps in building the pipeline. Adopting a DevOps process in Azure API Management using Azure APIM DevOps Resource Kit will also help in covering the dev-ops process.
I hope this helps and let us know if any questions.
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