How to only have excerpt in the timeline, and not the whole post ?

On my homepage, we used a “More” tag to shorten a post on the homepage and have a “read more” link. 
When add a new content,  in the content frame please put the cursor in anywhere you would like , and click on “More” button.
Please take a view below:

Or you can use this plugin to automatically shorten: Easy Custom Auto Excerpt
Regards,

Thank you 🙂

🙂