If I understand you correctly you need to make xyz.com an add-on domain to your main abc.com. That way you can publish the correct pages to the relevent sub domain and when your visitors navigate to xyz.com that is what they will get. You can learn more about this by
clicking here and viewing the appropriate tutorials. If, after viewing them, you still have questions feel free to use the search feature here (there are many posts dealing with adding domains) or ask another question.
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The moment one definitely commits oneself, then providence moves too. All sorts of things occur to help one that would never otherwise have occurred. A whole stream of events issues from the decisions, raising in one’s favor all manner of unforeseen incidents and meetings and material assistance which no man could have dreamed would have come his way. Whatever you can do or dream you can, begin it. Boldness has genius, power and magic in it. Begin it now. (William Hutchinson Murray)