The Inbox, Your View, and Actions pages are all located within the main Inbox page. The Inbox page can be accessed by clicking on the notifications icon which is located on the top navigation banner next to your global drop down and the search bar.
By default, clicking on the notifications icon will take you directly to your inbox, but any of the inbox pages can be set as the default view by clicking on the pin icon next to the page's name.
Your inbox is your one-stop place for all interactions surrounding you or your content. All likes, mentions, private messages, and following alerts are automatically sent to your inbox, as well as any notifications for content you have followed to your inbox. By default, all items you follow to your inbox will also generate email notifications. For more info on that, and customizing your inbox alerts, please check out Following.
Your View is a customizable page that allows you to see all of the content/people/places that are most important to you on one page. You can get there by clicking on your inbox notification box, and selecting “Your View” from the left-hand navigation. For more information on how to set up Your View, check out this doc: Your View.
The actions page contains notifications surrounding items that have been "marked for action" by you, or have been assigned as action items to you by another user. These notifications will remain in place until you or another member marks the item as resolved.