If you need to add a Read More link to your Articles and display it on the Front Page or as a News Article as a synopsis and want to be able to display the rest of the text if you click on the Read More link then Joomla! has an solution for you.
Create a New Article and add Content to it as you would do normally. Choose a Category and a Section
Select where the Article needs to be divided for for the Read More link.
At the bottom of the Editor there’s a Button called Read More that makes use of a Special Plug-In that divides the text into two sections, the synopsis and the full Article. Click on the Button it will add a Dotted Red line with indicates where the Article is splitted