Opentofu, also known as OpenTF, is an open-source Infrastructure as Code (IaC) tool that allows users to define cloud and on-premises resources using human-readable configuration files, which can be versioned, reused, and shared. This blog post provides a step-by-step tutorial on how to create and manage Harness entities by reusing existing Terraform scripts, highlighting the process of installing Opentofu, setting up the environment, and migrating from Terraform to Opentofu. The tutorial guides users through creating various Harness entities such as Organizations, Projects, Services, Environments, Infrastructure Definitions, Kubernetes connectors, GitHub connectors, and Deployment Pipelines using Terraform modules. The integration of Opentofu with Harness allows for automated, consistent, and efficient management of continuous delivery resources, ultimately enhancing deployment processes and enabling teams to focus on innovation and delivery.