I am working on a platform (www.dashboard.example.com) that has an admin site (www.admin.example.com). Each site is hosted on a different Google Firebase Hosting Project.
I want only certain people to be able to access the admin site. After some consideration, I found an IPSec VPN to be the best solution for me.
I also found that GCP offers a VPN service, but from what I can tell, it seems to only work with google compute engines.