Hi @Obaidur Rahman Syed ,
Thanks for reaching out.
There is no way to maintain IEF custom policies and user flows via Terraform. The only what you can manage via Terraform is B2C applications using the azuread_application provider.
You can refer Terraform official documentation is good with examples: https://registry.terraform.io/providers/hashicorp/azuread/latest/docs/resources/application
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/aadb2c_directory
Reference ARM API for B2C tenant creations and the Security section indicating the type of auth required: https://docs.microsoft.com/en-us/rest/api/activedirectory/b2c-tenants/create?tabs=HTTP
Hope this will help.
Thanks,
Shweta
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