Accessing the Wikis
The GitLab Wiki for each project is available from the project's home page. The icon to access the Wiki is in the left-hand navigation bar, and looks like a page with a bookmark. For example, for the Wiki project itself:
Click this and you will be taken to the top level of the Wiki.
You can navigate the contents of the wiki from here. Note the navigation column on the right of the page: This shows you the hierarchy of Wiki pages, and you can clink any page shown to jump to that item.
If you want to edit a page, take a look at how to edit pages.