I have never worked with Wordpress.
The Website has a page where we post PDF newsletters and I do not know how to add additional newsletters.
How do I post PDF newsletters on an existing page?
Log in first, create a post or a page. Then depending on how the previous pages look like, embed/attach PDF file or post link to the file.
1) You can just create a post + embed a URL.
2) Or might be there's a directory where PDF files are stored.
3) Might be a completely different approach being used on your site.
Suggestion: Post the URL of one of your PDF download pages. Likely someone can help you decode how to duplicate what's being done.
What theme are you using?
Are the pdf's a list of links that when clicked the pdf opens up? Or are the pdf's embedded on the page? By embedding on the page, I mean you go to yoursite.com/somepage where you see your site header and footer. In the body you can view the pdf file.
When you click on the link the PDF is downloaded to the computer.
They key was your comment Uploading the pdf document using "media".
I clicked around, first determining there was an UnDo button, and figured out how to upload the PDF's.
My work is not pretty, but I got it done. The Website in question over a year behind in uploading newsletters: http://moph-chapter-750.com
There is one issue though. Your links are going to http://dev.moph-chapter-750.com/wp-content/uploads/2016/04/heartbeatMAY13.pdf and not your live domain. As a quick fix, in Wordpress Admin, go to Settings > Permalinks. Make sure the correct option is selected and hit save changes. Then re upload your files and set the links. If that does not fix it, then open a new question for this specific function.
It opens normally now. I opened the page and the Post name was toggled so I switched to Plain. One other small issue is resolving a bad link. When you click on Home page "Communications" you go to a page with two choices and clicking on Chapter 750 Communications is a bad link. I have no idea where to change or how to change the link. It's a minor issue compared to updating the newsletter postings. I'll keeping clicking around.
Thank you again.