How to add secrets to Eclipse Github (specifically for pushing to the container registry)

What is the "correct" way to push packages to the Github docker registry at ghcr.io from Github Actions?

Currently we do it "by hand" using PATs. To do so in Github Actions, secrets are needed, however the necessary "setting" tabs is not accessible by ourselves.

What is the process here? Are there already some secrets on orga level, that can be used? Or do we need to request adding tokens on a per-repository basis here?