Replacing the_content to the_excerpt() for short posts.

Hello. I am trying to have my posts display short version on a post page.

I am using twentyfourteen template
I set my posts to display on a custom page, not in home page.
I went to wp-content >>> themes >>> twentyfourteen >>> content.php
and replaced the_content with the_excerpt.

Now my custom posts page displays short versions of the posts, but there is no link to the full version of the post.

I do not want to add “read more” manually to each post
I do not want to add excerpt manually to each post

According to codex replacing the_content with the_excerpt will automatically display first 55 words of the post. It does but there is no “read more” or anything else to the full post in the end.

Please advise.

Thank you in advance!