Post Links

I’m new to WordPress and hired a group to design my site. Unfortunately, they know less than I do. I’m using WP as a CMS and have several medical categories. When I try to add articles to each category, the result is a small font headline link with only 2 lines of content. I need to “grab” the first paragraph and increase the size of the headline font. Any help pointing me in the right direction would be great.

Thanks in advance!