i did bought a domain "X.com" and i design the website under this domain using Wordpress.
i finished all the settings, theme and plugins i want to configure on this "X.com" domain.
now i bought a new domain "Y.com"
what i want to do is to copy all settings, Theme, Plugins etc.... that i did on "x.com" to "y.com"
can anybody guide me please.
Step 1. Make sure the hosting has the intended domain on it and the files are in the proper location.
Step 2. Go into the wp-config.php file and add lines of code as seen in this doc (https://codex.wordpress.org/Changing_The_Site_URL)
Step 3. Make sure the domain is resolving to the proper ip address on the hosting account.
A WordPress installation consists of a set of files and a database. You could use a backup plugin (see article "7 Best WordPress Backup Plugins Compared (Pros and Cons)") to backup x.com and restore it to y.com.
If you intend to always keep both sites identical, you could create an Alias (whereby y.com would automatically display the contents of x.com) or redirect y.com to x.com.
These GoDaddy help topics should get you started:
I haven't done this in while so someone else might be in a better position to help you with the domain settings, but at least you know your options.