We highly apologize for late reply. I hope we still can help you with some suggestions.
If you are developing a site with not-too-many functionality, I think you are, more or less, in the right track. But still you can’t add your page (which you haven’t published yet) in the menu.
In development world, we use staging site. A staging site is:
“Staging site, in website design, is a website used to assemble, test and review its newer versions before it is moved into production – Wikipedia”
As it says, we used to have two sites with everything exactly same. One in production server, and one in staging server (server for staging site). We test in staging site and when we are done, we push the update in live site in the production server.
You can consider your localhost as your staging server too but it’s always better to have same server configuration in both the places. But if you work on localhost, you can move the whole site to production if you want and we have a wonderful FREE plugin called “Domain Replace” for replacing all URLs. Like replacing all existance of “http://localhost/” to “http://www.your-domain.com/”. You can download the plugin from here: https://wordpress.org/plugins/domain-replace/
I hope it helped. Feel free to ask if you have any other questions. Have a nice day.