@Mr. Banana The issue is with the starting double quote in your request. You can try the below curl command on your windows machine, just replace your resource key in the header.
curl -v -X POST "https://api.cognitive.microsofttranslator.com/translate?api-version=3.0&from=en&to=es" -H "Ocp-Apim-Subscription-Key: <your_key>" -H "Content-Type: application/json; charset=UTF-8" -d "[{'Text':'Hello friend.'}]"
Also, you do not need all the headers, see the documentation reference here.
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and Yes
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