To use a starter workflow provided by your organization, you need to go to the Actions tab in the repository and select New workflow. This option allows you to either create a new workflow or select from a list of available workflow templates, including starter workflows provided by your organization.

GitHub Actions supports the use of service containers, which allows you to spin up a PostgreSQL database (or any other service) in a Docker container during your workflow. You can pull a PostgreSQL image from Docker Hub, and the container will automatically be available to your workflow job. This method requires no additional infrastructure and is easy to configure and maintain, as you simply define the container in the workflow file.

Creating a Docker container action
Create a dockerfile
Dockerfile support for GitHub Actions
When creating a Dockerfile for a Docker container action, you should be aware of how some Docker instructions interact with GitHub Actions and an action's metadata file.
Creating an action metadata file
Create a new action.yml file.
Reference:
https://docs.github.com/en/actions/tutorials/use-containerized-services/create-a-docker-container- action
https://docs.github.com/en/actions/reference/workflows-and-actions/dockerfile-support

Some actions may require a GITHUB_TOKEN as an input to authenticate and perform specific tasks, such as creating issues, commenting on pull requests, or interacting with the GitHub API. In such cases, you would need to explicitly pass the token to the action.
When making an authenticated GitHub API request, the GITHUB_TOKEN is required to authenticate the request. This token is automatically provided by GitHub in the workflow, and it must be explicitly used when interacting with the GitHub API.