[E] To bypass GitHub's limit of 100 MB you can use Git Large File Storage (Git LFS). It stores references to your file in the repo by creating a pointer file. However, the actual file is going to be stored at a different location.
[C] Configuring the retention period for GitHub Actions artifacts and logs in your organization You can configure the retention period for GitHub Actions artifacts and logs in your organization.
By default, the artifacts and log files generated by workflows are retained for 90 days before they are automatically deleted. You can adjust the retention period, depending on the type of repository:
For public repositories: you can change this retention period to anywhere between 1 day or 90 days.
For private repositories: you can change this retention period to anywhere between 1 day or 400 days.
When you customize the retention period, it only applies to new artifacts and log files, and does not retroactively apply to existing objects. For managed repositories and organizations, the maximum retention period cannot exceed the limit set by the managing organization or enterprise.
Reference:
https://gitprotect.io/blog/github-storage-limits/
https://docs.github.com/en/organizations/managing-organization-settings/configuring-the- retention-period-for-github-actions-artifacts-and-logs-in-your-organization