How to link

Suppose there are 2 different posts. Post 1 and 2.

There are some thing that is not explained in 1 and that is explained in 2 . What i do is link the part of 1 to 2 so that the reader can better understand it.

Now can this be auto done.
I dont link it the plugin does. Is there a plugin.
The plugin find suitable keywords and link them to other posts all within my website posts and links to it..

For better example see https://en.wikipedia.org/wiki/Good_Entertainment
Just an article see most words are linked to other pages.

How can i do it using a plugin
Help