Publishing actions in GitHub Marketplace
You can publish actions in GitHub Marketplace and share actions you've created with the GitHub community.
Prerequisite include:
[B] Each repository must contain a single action metadata file (action.yml or action.yaml) at the root.
The name in the action's metadata file must be unique.
The name cannot match an existing action name published on GitHub Marketplace.
[C] The name cannot match a user or organization on GitHub, unless the user or organization owner is publishing the action. For example, only the GitHub organization can publish an action named github.
Reference:
https://docs.github.com/en/actions/how-tos/create-and-publish-actions/publish-in-github- marketplace

[D] To authenticate to a GitHub Packages registry within a GitHub Actions workflow, you can use:
*-> GITHUB_TOKEN to publish packages associated with the workflow repository.
* A personal access token (classic) with at least read:packages scope to install packages associated with other private repositories (GITHUB_TOKEN can be used if the repository is granted read access to the package.
[E] You can use the GITHUB_TOKEN to make authenticated API calls. This example workflow creates an issue using the GitHub REST API:
Reference:
https://docs.github.com/en/packages/learn-github-packages/introduction-to-github-packages
https://docs.github.com/en/actions/tutorials/authenticate-with-github_token

GitHub only lists actions from repositories that are visible to everyone. This is a firm requirement for publishing an action to the Marketplace and private or internal repositories cannot be listed.

A deployment workflow can be started after a build workflow has finished by using the workflow_run event in the deployment workflow's on trigger. You must specify the name of the build workflow you want to trigger on and use an if condition to ensure the deployment workflow only runs if the build workflow successfully completes.
Here's how to set it up:
In your deployment workflow file: (e.g., deploy.yml), define the on: trigger.
Use the workflow_run event: within the on: trigger.
Specify the build workflow: by its name.
Add a conditional if statement: to the workflow to check the conclusion of the workflow_run event, ensuring it equals 'success'.
Reference:
https://docs.github.com/actions/learn-github-actions/events-that-trigger-workflows

Downloading workflow artifacts
You can download archived artifacts before they automatically expire.
Who can use this feature?
People who are signed into GitHub and have read access to a repository can download workflow artifacts.
Reference:
https://docs.github.com/en/actions/how-tos/manage-workflow-runs/download-workflow-artifacts