Build a simple website

Hi, i am new in this type of website environment. I need some one teach me how to develop a website like [login to view URL] OR http://www.mobincube.com. You don't need to make a full like what u see. What i need is simple one 1. I want to learn coding how user drag drop widget to model phone on page (at least login widget & signup) 2. User add information (Page title, page header & so on) 3. User click save and it will Convert it to android APK, IOS OR windows platform... It is not a big project, it is just 4-5 page... Ignore the design, you can make it white blank page as long the function is running like those website. Thanks... Max budget is $50 due to simple blank project with simple function that can operating like [login to view URL]