This theme template is designed in such a way that virtually all the content on the site is editable without touch any code.
To get to any the editor of any page you go to Dashboard>Website>Law Enforcement Action Network and that will bring you to the list of pages. You will see to the right of the blue highlighted pages Top Nav. To change the order of pages in the top nav, just drag and drop them into the order you want. Next to that, you will see Supporter nav. That is where you change the text and links to the three big buttons in the Sidebar Navigation that appears on many interior pages.
The large hero image on the homepage is the site's Header Image. This can be changed by going to Website>Law Enforcement Action Network>Site Settings>Header Image. Remove the current image and upload a new image. This is the default Header Image for every page of the site. However, we have added a little code into the layout.html file that allows you to override the default header image on any page by going to that page (Click on the edit icon on the left on the list of pages) go to Files and click on the Select files to upload and upload an image (I recommend a size of 1200 x 400). Before you do, rename the file so it has the word banner in it, ie., Law_Enforcement_Action_Network_About_banner.jpg. Note: Images are extremely search engine friendly. Including the site name will enhance the visibility across multiple platforms.
The slogan of the homepage is in the content of the homepage. You would go to Home>(Click on edit icon)>Content and then just change the text. As I don't foresee you changing the logo, that is actually hardcoded into the home_hero file.