JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <input placeholder="Адрес почты для подписки" id="subs_email" name="subs_email" type="email" />
    <button id="subscription_form" type="button">Подписаться</button>
</form>

JavaScript

var $form_input = $('#subs_email').val();
var $form_input2 = document.getElementById("subs_email").value;
var $formData = {
    'subs_email': document.getElementById("subs_email").value
};
$('#subscription_form').click(function () {
    console.log($form_input);
    console.log($form_input2);
    console.log($formData);
    console.log(document.getElementById("subs_email").value);
    console.log($('#subs_email').val());
});