Scroll To Top plugin does the job with just one click a button appears when a person scrolls to the middle of the page to be clicked on.
This Plugin adds a scroll to top button in your site
Easily create and manage a page scroll to top
Scroll Top Advance plugin allows the visitor to easily scroll back to the top of the page also navigate to the specific "ID" or "class&
WP Scroll to top is beautifully designed and supper plugin.Very easy to use and perfect functionality.