"To add this section" means to include or insert this particular part into something, typically a document, text, or a larger piece of work. Full definition
I was actually wondering if it would be a good idea to add a section on free dating site for people who are willing to take part in long - distance relationships. (christian-dating-service-plus.com)
I will most likely add a section of the site all about the garage. (humblemechanic.com)
Optional extras: Some people like to add a section about personal skills and hobbies. (inspiringinterns.com)