How to become admin for project?

I’m trying to get to the admin area so I can set the time-to-live for the gitlab container registry token. However, I don’t see where that’s available to me. I am the sole owner and creator of the project after I signed up for a Gitlab account and clicked to create a new project. My problem is similar to this person:

except I’m not using Gitlab CE.

So how can I become an admin for my own project so I can change some admin settings?