identify language in browser

Hello, I found this plugin at the suggestion of a speaker in a semrush video where I understood that the tag, in addition to indicating to Google which url is for each language, would have the ability to identify the language of the user’s browser and thus show him the content in your language —if it were available— however, this does not happen since our browser is in Spanish and continues to show us the version that we have created in English.

I would like to know how to solve this.

Thank you.

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