I did it from JSON to XML but I don know how to get data from an excel file.

document.getElementById('btn-convert').onclick = function() {
    var x2js = new X2JS();
    var new_xml = x2js.json2xml_str(JSON.parse(document.getElementById('json').value));
    var pretty_xml = vkbeautify.xml(new_xml, 4);
    document.getElementById('xml').value = pretty_xml;
};