This does not appear to belong in Suggestions and Feedback, and appears to be a request for help.
I am moving this to the osTicket 1.7 > Installation and Setup Help section of the forums.
You can use whatever URL you want to use, but you will have to configure your webserver to serve it, and/or configure DNS (of course will have to own the domain or have access to using the domain you want to use.) Once you have configured your webserver to serve the page make sure that you log into osTicket and set the Admin panel -> Settings -> Helpdesk URL to what you have chosen.