Changing IP/URL and Port on A Newly Installed Locomotive Site

Hello,

I am completely new to Ruby and RoR, and ofcourse LocomotiveCMS. Fortunately, I have managed to follow the instruction at https://locomotive-v3.readme.io/docs/getting-started-with-locomotive until bundle exec rails server, eventhough I have to install node.js and puma before that, which are the missing requirements from the docs. I did it directly on my VPS. So my question are:

how to change the IP/URL (and the port) so that I can change localhost with my IP/URL?
What to do after bundle exec rails server and register to my site as user? I am not sure what to do to follow section Pushing a site template with Wagon at https://locomotive-v3.readme.io/docs/getting-started-with-locomotive.

Thanks!