This depends on how you want to have your data. But for example if you need parent and child on the same row, you could try something like
SELECT t1.EmpId, t1.EmpName, t2.EmpId, t2.EmpName
FROM table1 t1 left outer join table2 t2
on t1.EmpId = t2.ParentId
Addition, recursive example
WITH Employees(ParentId, EmpID, EmpName, Level) AS (
SELECT t1.ParentId, t1.EmpID, t1.EmpName, 0 AS Level
FROM table1 t1
WHERE ParentId = -1
UNION ALL
SELECT t2.ParentId, t2.EmpID, t2.EmpName, Level + 1
FROM table1 t2 inner join Employees e
ON e.EmpId = t2.ParentId
)
SELECT ParentId, EmpID, EmpName, Level
FROM Employees