Adding a blog to an already created dynamic front page

I have an already created site with 5 existing posts and 7 pages with sub-pages. I’m trying to create a blog but when I follow the instructions to create a static page, the appearance of my site changes from dynamic to static. Can anyone please tell me how to maintain my dynamic page while, at the same time, creating a blog? While we created the content for the site and I maintain it, someone else actually created it using WordPress, and they are nowhere to be found. I’ve learned a lot, but I am FAR from a techie. Any help will be greatly appreciated.