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Hi Cristiana Answering your question, I will say that canonical-tag to a site is not an option is a requirement, almost mandatory requirement. The canonical tag is directly related to the duplicated content issues. From a technical standpoint, you'll need to understand how duplicate content can unintentionally be added to a site. Many times, it's simply a canonicalization issue. For example, homepage canonicalization causes most duplicate content issues on sites. For example, search crawlers might be able to reach your homepage in all of the following ways: https:yoursite.com https:www.yoursite.com http:yoursite.com http:www.yoursite.com http://example.com/index.php Just to give you an example on Google Search Console you need to verify these versions of a single domain for single property http:www.yoursite.com https:www.yoursite.com http:yoursite.com https:yoursite.com Google will see each URL as a different page – and it won't know which one you prefer to send users to. The problem can get exponentially worse if it exists on every page on your site. The easiest way to solve the problem is with a server-side redirect that sets one of those URLs as the “official” version of the page, and only serves that version, regardless of which URL was the destination. You can also use the rel canonical tag – it's a directive that's inserted in the header of the page. It looks like this: rel='canonical' When you're starting SEO on a new site, you'll want to check out all of the canonicalization that's been declared, so that you have a solid understanding of what's going on with the site content.

Hi Cristiana, It sounds like you need to implement hreflang on your sites. Hreflang can be complicated but you can start reading about it and how to implement it here: https://moz.com/learn/seo/hreflang-tag Cheers, David