To access the place to upload your website: login to your cPanel or relevant control Panel.
Find the FILE MANAGER
Search for the public folder, in most cases named: public_html
Files added here will reflect on the internet if your hosting package is set up correctly and your domain is resolved.
To text, add a file called: index.html and or index.php
In this file add in some text, eg: 'Its working'
Add your domain in a browser on a system linked to the internet.
You should see the above text in your browser.
If not please contact support to investigate further.