Help me - I am stupid

Hi.

I need your help.

I managed to install Tailscale on my devices I want to connect (NAS, Android Phone, Chromebook).

The devices are shown as “connected” in the dashboard.

If I try to connect to a service from one device to another, I get a timeout - not matter what service I try to use (i.e. Plex Server, NAS Web Frontend, etc.).

What am I doing wrong?

Is there anything special I missed?

Do I have to open specific ports on my router?
BTW: I use a FritzBox with a dualstack IP connection to my ISP.

Thank you for any hint that leads me in the right direction.

im stoopid too but maybe try checking in the services tab and checking if the right ports are active or something lol