Making a jellyfin server behind a double NAT

[Hectik]

I have recently downloaded jellyfin so I can watch some of my stuff from my computer on the big TV screen without needing to move files, But now I'd like to be able to stream it to my girlfriends TV and maybe some of my friends, I tried setting it up with Tailscale but it seems like it would require me giving my credentials to other people/needing to bee their physically to log in which sounds like too much of a hustle, plus it looks like they'd have control over my Tailscale account.
Now I wonder if theres a way to setup a jellyfin server while being under a double NAT or GCNAT thats fairly easy to setup and would also work on an android TV that doesn't require my credentials, also if its possible to accomplish that without using a third-party app besides Jellyfin?

Actually you can sign in for them remotely, this is how I've set up access for my friends and family. When asked to login to Tailscale on the device you want to give access it will open a browser with a unique link, you can ask that person to send you that link and you login or alternatively they can use the QR code login option and send you the image.

Edit:
This will not give them access to the account used to login to Tailscale, i.e Google SSO etc or to tailscale admin. All tailscale apps are just clients (nodes), for now, the only way to manage Tailscale admin is through their portal.