Sure
SELECT EmployeeID, "SKILL1" AS SkillID, SKILL1 AS Level_OF_Knowledge WHERE SKILL1 IS NOT NULL
UNION ALL SELECT EmployeeID, "SKILL2" AS SkillID, SKILL2 AS Level_OF_Knowledge WHERE SKILL2 IS NOT NULL
UNION ALL SELECT EmployeeID, "SKILL3" AS SkillID, SKILL3 AS Level_OF_Knowledge WHERE SKILL3 IS NOT NULL
*repeat last line for each additional column in your first table