This is the most basic View. It shows a single Entity details with all its collections and relations. When you create a new Database, it automatically has Entity View:
What you can customize on Entity View?
Re-order Fields using drag and drop
Choose visible Fields in Collections
Add new Fields and Relations
You may also jump into Database customization. Click … and select Edit Database.
Mind that the changes will affect not only the Entity you’re looking at, but all of the Entities of this Database.