I want to upload my files

1. I can use FTP, but how to setup it ?
Let's say my my account is XXXL , http://XXXL.BizHat.com
I have CUTEftp
- what should I write in "Host Address" field ?
- user Id, should be "XXXXL"
- password is my password
My problem is with Host Address field

2. I can login to http://www.domainstobuy.com/login.php
and then use File Manager
Well, when I click on File Manager line, I can see the custom
"index.html" but I cannot see how to upload other files.

Please help me
Thank you for your time and attention
vd