Port forwarding not working in iOS

[last-Programmer]

Hi,

I have installed alpine linux arm64 edition in iPad Pro M1 and setup visual studio code server using http://coder.com and the coder server listening at port 3000. I forwarded the port in network setting to hosts 3000 port and when i try to access http://localhost:3000 i am getting error message unreachable. coder.com creates a tunnel and gives public url and when i access it with public url it is working.

Any help would be appreciated

Thank You