Alright what is best why to Transfer a site and what do I have to do to get it ready? Do I use root and password of the WHM coming from.. or the username/owner of the site transferring?
The way you're doing it is the easiest way - use root and a key (or password if you didn't set up a key), if you have multiple sites you're moving from there there is also the "Copy multiple accounts from another server".