Ongoing Dev once page is published

Questions
1

I am Brand new here and to the Dev world. so this question might seem obvious to some. My question about how the web app development works.
If I am using a Template to modify and build my first web app, so first I just want something simple it will be a blog site and publish it, after that I want to create an area that other people can log in and post ~“their 2 cents worth”. Then I will have a downloads section where people can buy and download digital products we will have.
Now the question, can I have the blog published and then be working on the other areas and not have them publicly visible? can I create these in other pages that are not published or do I need to create them in separate apps then combine the “new app” with the existing published “Blog app”?

Looking forward to your help and answer and my apologies if this is a silly question for you mor experienced folk

Regards
Sii

2

Yes, the live version and development version are separate. The live version is what users can access. The development version is where you make changes. When you’re done making changes, you deploy it to live.

3

Fantastic, It makes sense that it would be that way but I just wanted to make sure.