If firstname.lastname@example.org is the email your new account is registered on...
You currently have only one website.
Your website is loading just fine.
(please, correct me if I am wrong..)
And two, the same question I asked previously...how to upload files to a subdomain?
Create a new connection in FileZilla (use plain FTP).
• Host is files.000webhost.com
• Username: your website's name (without '000webhostapp.com')
• Password: your website's password
• Use plain FTP as connection (no security, no encryption)
You can connect to File Manager as well, and access your website's content. (use website's username/password as credentials)
Your instructions only allow me to upload to the principal web page (the one that ends in 000webhostapp.com) but not to my newly created subdomain.
Your newly created subdomain (although I see only one domain parked to your account) is pointing to your main website, which ends in 000webhostapp.com. Upload your files to your main website, and they'll be shown if you access through the browser the newly subdomain