@haggarwal25

Best is slightly subjective as it really depends on your needs specifically :-). One of the best things you can implement is caching, in which case I'd recommend WP Super Cache and W3 Total Cache.

WP Super Cache is easier to setup and requires far less configuration. W3 Total Cache, on the other hand, is far more complex and offers way more options. If you prefer to be hands on, and want total control over caching and need options when it comes to how caching is handled (Redis, OpCode, Memcached, File Cache, etc), W3 Total Cache would be the plugin for you :-).

https://wordpress.org/plugins/wp-super-cache/

https://wordpress.org/plugins/w3-total-cache/

W3 Total Cache also offers easier CDN integration, so if you're offloading assets (images, CSS, JS, fonts, etc) to a CDN that's supported, that's another benefit.

I also generally recommend iThemes Security (Better WP Security), as it can help on the other end of the spectrum by providing a pretty complete security suite to deter would be attackers.

https://wordpress.org/plugins/better-wp-security/

@haggarwal25

I support jtittle's recommendations for plugins. A reliable caching solution is the most important factor regarding page performance.

However, because you might be using a VPS for your site, I would also check out https://easyengine.io/.

If you are using easyengine.io with its --wpredis option you are getting a perfectly calibrated WordPress install with super fast Redis caching out of the box. A site created with easyengine will perform much better as any custom WordPress VPS-setup with a caching plugin.

Additionally, you are also getting stuff like

• easy let's encrypt integration
• wpcli out of the box
• an easy way to serve http2

Another important thing is choosing the right theme. Most of the standard themes are bloated multipurpose themes without any focus. Using something like this will impact your site's speed negatively.

However, with a plugin like https://wordpress.org/plugins/fast-wp/ (https://www.velocious.io/plugins/fast-wordpress/) to optimize your CSS and JS file serving you can work miracles.

An image-optimizer like https://de.wordpress.org/plugins/optimus/ (https://optimus.io/en/) will give you additional advantages.