Address bar/domain

I have set up a wordpress site with Just Host – https://www.xcel247.com/thistle/. The domain https://www.thistlechannel.tv (hosted by another provider) has been redirected to Jost Host by changing the nameservers. I have used “add on domains” in C panel to pointt https://www.thistlechannel.tv to the file xcel247.com/thistle/. On the first page of my wordpress site the address bar shows https://www.thistlechannel.tv as my client requires – but not on subsequent pages. I do not want to use framed masking – but need the address bar to reflect the domain not the source wordpress files. Can this be done? As an example see https://www.ikodum.com/ (a theme demo). I need to achieve the same look in the address bar which reflects the domain and domain pages as in a traditional website.