We are using MailChimp for WP plugin for Newsletter subscribe. You can read more about MailChimp from here​
Follow that step below to help you can collect email of subscribers.
Step 1 - Signup for Mailchimp account then create your lists to collect email
Step 2 - Install and active plugin MailChimp for WP​
Step 3 - Navigate to MailChimp for WP > MailChimp then connect with your mailchimp account you created from step 1
Step 4 - Create mailchimp form to collect email. Navigate to Forms
Import HTML Code below on section Form mark-up Source
Source :
<div class="form-style-1 newsletter-footer clearfix">
<h4>Sign up for Newsletter</h4>
<p class="textwidget">
Sign up for our mailing list to get latest updates and offers
<div class="input-group">
<input id="mc4wp_email" class="form-control" name="EMAIL" required="required" type="email" placeholder="Your email address" />
<div class="input-group-btn">
<input class="btn-primary btn" type="submit" value="Subscribe" aria-hidden="true"><i class="fa fa-envelope-o"></i>
Step 5 - After creating from of your plugin. You must set position where you want to display.
Going Appearance -> Widgets then drag mailchimp widget to Newsletter Sidebar. You can bring that sidebar to every position you want. ( You can drag to left, right sidebar for each page. You can drag to Footer position.... )