Steps

<script type="text/javascript" src="https://www.google.com/jsapi"></script>

<b>English to Hindi</b> : <textarea id="transliterateTxtBox"></textarea>

<script type="text/javascript">
        google.load("elements", "1", {
            packages: "transliteration"
        });

        function onLoad() {
            var options = {
                sourceLanguage:
                    google.elements.transliteration.LanguageCode.ENGLISH,
                destinationLanguage:
                    [google.elements.transliteration.LanguageCode.HINDI],
                shortcutKey: 'ctrl+g',
                transliterationEnabled: true
            };

            var control =
                new google.elements.transliteration.TransliterationControl(options);
            control.makeTransliteratable(['transliterateTxtBox']);
        }
        google.setOnLoadCallback(onLoad);
</script>

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