Your index page does not show anything; the HTML form is not here, perhaps somewhere else. However, the problem you are facing is, because you are using HTTP GET communication verb. You need to use POST verb, to hide all of that information from URL and add in the headers or body of the request.
Fix is as simple as,
<form method="post">
<!--
</form>
Once this form gets published, it will submit the form data, by adding the form information in the body of the request and not in the URL.
For more on this please read,
HTTP request methods - HTTP | MDN[
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<form> - HTML | MDN[
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