Subdomains pointing subdomains urls with same pages than domain

Hello,

I wanted to know if you know a way that subdomains get the same pages than the main domain but with “subdomains urls” inside the pages.

It’s hard to explain but here is an example: My domain is “www.mywebsite.com”, I create subdomains like “affiliate1.mywebsite.com”, “affiliate2.mywebsite.com”, etc. I want that these subdomains display the same pages than my main domain, but the problem is when I redirect the subdomains to the root, even if urls work, links inside display the “www.mywebsite…” form, and I would like they display the “affiliate1.mywebsite…” or “affiliate1.mywebsite…” form (for opening pages, articles..).

How can I get those results. Is there any plugin or a code to succeed?

Thank you in advance for your help (and sorry if I don’t explain well in english).

Thomas