From the GitHub UI, very simply. Go to a repo you administer, in the /tags page, and each tag has a ... Drop-down menu with a delete option. Then upload a new tag by that name.
Tags are not automatically updated from remotes on pull (they are automatically created locally if it's a new tag). This doesn't mean that the remote can't change what the tag points to, only that it's easy to spot.
Edit: and to be clear, for many years after release, this was the recommendation from the Visual Source Safe team (Yes, that team developed GitHub Actions) for managing your actions. Tell people to use "v1", then delete the tag update it each time.
Tags are not automatically updated from remotes on pull (they are automatically created locally if it's a new tag). This doesn't mean that the remote can't change what the tag points to, only that it's easy to spot.
Edit: and to be clear, for many years after release, this was the recommendation from the Visual Source Safe team (Yes, that team developed GitHub Actions) for managing your actions. Tell people to use "v1", then delete the tag update it each time.