You can create a query to filter for one specific employee. Follow the steps below to query for one employee:
Go to the Core, Leave, or Payroll module.
Click Query Setup and click New.
Enter Query ID, e.g., One Employee.
Enable the Name checkbox and set the Employee from and Employee to fields to the same employee.
Click Save, then Apply.
This activates your query for the selected employee. You can use this query before generating reports or payslips.