The Employees table uses EmployeeId as the primary key, creating a clustered index that sorts data in a B-Tree structure. This includes a root node, intermediate levels, and leaf nodes containing sorted data rows. For example, querying an employee with ID 1120 involves navigating from the root to the appropriate leaf node in a few steps for efficient retrieval. The structure uses pointers to quickly locate data, with each data page holding up to 200 rows in this scenario. SQL scripts demonstrate table creation and insertion of one million rows to illustrate this process.