There are many way to speed up your Wordpress Website like delete unused plugins, install high-quality plugins only, use a lightweight theme and Optimize images, etc
But the easiest way to Speed Up your wordPress site in by Wordpress Plugin - WP Super Cache. This plugin generates static html files from your dynamic WordPress blog. After a html file is generated your webserver will serve that file instead of processing the comparatively heavier and more expensive WordPress PHP scripts. 99% of your visitors will be served static html files. One cached file can be served thousands of times. Other visitors will be served custom cached files tailored to their visit. If they are logged in, or have left comments those details will be displayed and cached for them.
Please check out here: https://wordpress.org/plugins/wp-super-cache/