Please refer to codex.wordpress.org/Managing_Plugins#Automatic_Plugin_Installation.

Adds PACE page loading progress bar to your website, with live preview at the admin panel and dynamic color changing.

Add a CSS3 effect to your blog while loading pages. 給你的部落格增加一個帶有CSS3效果的頁面載入動畫

Easily add a stylish Laser Loading bar like YouTube & Medium.com to your site. Indicates page loading progress at the top.

A simple plugin to enable lazy loading for all images using WordPress image functions.

Lazy Load for WordPress images bosst your website loading speed. Load images only when required. Show images than after scrolling down and when viewport and Lazy Load Background Images loads then Improved page speed.