WordPress Widgets add content and features to your Sidebars. Examples are the default widgets that come with WordPress; for Categories, Tag Cloud, Search, etc. Plugins will often add their own widgets. To activate the widgets, go to Appearance > Widgets and click and drag a widget from the Available Widgets section and drop it into of the General Sidebar, Footer Siderbar 1, Footer Siderbar 2 and Footer Siderbar 3, Footer Siderbar 4 or Custom Create Sidebars widget areas.
TheFlow have 6 Special Widgets for your blog that improve default WordPress widgets functionality, we recommend you to use this widgets instead of default:
About Widget: Displays for specific about author.
Instagram Widget: Allows you to display your latest Instagram photos.
Recent Posts Widget: Displays new posts.
Social Widget: This widget will display social media shared counter of your choosing from a variety of popular networks.
Newsletter Widget: is used to save users emails.
Category Slider: You can list the articles of the categories you want.
1-)MailChimp Sign-Up Form (Newsletter)
MailChimp for WP > Forms to open the page. Add the following code to the form.