I am trying to rejig/ reordering my navigation items on the page header. there are 3 items. FAQ, Contact us and Service offering. I want to reorder as Service offering, FAQ and Contact us. I can’t find a way to do that. can you help?
Visit the Dashboard Sitemap and reorder the pages how you’d like them to appear 
In addition to @enlil 's answer, another possibility is that the navigation block (usually auto-nav) might have display options such as “alphabetical”, “sitemap order”, etc. Enlil’s suggestion will definitely work if that option is set to “sitemap order”.