Your free JoonWeb URL is in the format (yoursitename.joonweb.com). The site address section of the URL is not editable. This URL has been auto-created according to your entered site name.
It's your choice whether you want to purchase a Premium Plan or not, till then, you can continue using the free trial JoonWeb URL if you want to insert your own domain name then connect your domain to your JoonWeb website.
In order to connect your domain to your JoonWeb website, you will have to purchase one of our premium plans accordingly.