In order to change the domain that your website would work with you should open your WordPress administrative area -> Settings -> General.
Under the WordPress address (URL) and the Site address (URL) fields enter the domain that you wish your application to work with and save the changes.
In this way your website will work with the newly specified domain name.
The same modification is valid if you want to add "www" to your domain.
WordPress is a powerful software that is easy to work with once you have the right host to support you. Before you lose any more time with the wrong host, check out the SiteGround WordPress hosting offer.
