sendgrid_mail.js

function sendmail(){
  var name = document.getElementById("name").value;
  var lastname = document.getElementById("lastname").value;
  var email = document.getElementById("email").value;
  var phone = document.getElementById("phone").value;
  var country = document.getElementById("country").value;
  var project = document.getElementById("project").value;
  var contact = "Email";
  var comment = document.getElementById("comments").value;

  $.ajax({
    url: "https://api.sendgrid.com/v3/mail/send.json",
    type: 'POST',
    beforeSend: function(request, settings) {
      request.setRequestHeader("Authorization", 'bearer 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');
    },

    data: {
      "personalizations": [{
          "to": [{
              "email": "samahel021@gmail.com"
            }]
        }],
        "from": {
          "email": email
        },
        "subject": "Contacto",
        "content": [{
          "type": "text/plain",
          "value": "<p>Nombre: " + name + " " + lastname + "</br>" + "Teléfono: " + phone + "</br>" + "País: " + country + "</br>" + "Proyecto de interés: " + project + "</br>" + comment + "</p>"
        }]
    }
  });

}