when i try to access my site i get "This site is under construction" can someone tell me why

OS: windows

Yeah you have not made your website yet or published it

that is the placeholder index.html page you get when you sign up for a free subdomain or even a domain after it is propogated.

so now all you need to do is start building your site save it as index.html and publish

but how you make your site and more is up to you.