I think the question is not about configuring one’s gateway, but to know on what port connecting to a remote, out-of-our-control getaway.
I have no control over ipfs.infura.io but I know it’s a getaway. Connecting to ipfs.infura.io:8080 gives an error (because it should be port 80). I guess the question is: how can I ask Infura.io to tell me on what port I should connect to it (so it answers “Connect on port 80. The default 8080 won’t work”)?