So I took a long time to try make the Visual studio code get working but it turned out keep mention couldn’t find .Net 8 even I already installed, so I gave up on this way.
Then I figured out the server app have json file to control what port listening, then I edited the 80 & 443 port in listening address to 8080 & 4430 port, the server app was running without issue.
However, the game itself really depend on 80 & 443 port, so not ideally to change those ports like that.
May I know if there any method to let the server app bind to 80 & 443 port?
Some article suggested to use sudo setcap CAP_NET_BIND_SERVICE=+eip but I tried that still not work and I assume that just for native linux app. 
Did you actually allow the EXE to bind? It must be whatever opens up the network port
sudo setcap CAP_NET_BIND_SERVICE=+eip /path/to/some.exe
Note that this needs to be re-run if you build it again 
There’s another method called authbind - need to permit access to those ports and then run your command using authbind. Plenty of examples out there.
Finally, Plan D: -
Set up a firewall/proxy that NATs/forwards all the traffic to the new port, and clients just connect to that
Thanks for your reply and yeah, I used sudo setcap CAP_NET_BIND_SERVICE=+eip for the .exe file and even set to wineserver and winepreloader in runner folder but nothing work.
I also heard authbind which searching but seem this package not installed in steamos, and I don’t know how can I get it from pacman
If talking about firewall setup to redirect port, seem quite hard to do it in SteamOS, but well, I think I will still try to see what I can do. 