You can log into Website Builder by navigating to https://www.uwwweb.com/hosting . If you're not logged in, you will have to do so. This page will redirect you to a listing of all your Hosting products. Click on the "Manage Hosting" button and you will be directed to the hosting login page. Log into this page using the username and password that was provided to you upon purchasing your Hosting product.
Alternatively, you can type in admin.(domain name) into your browser.