delete duplicates using CTE

WITH CTE([FirstName],
    [LastName],
    [Country],
    DuplicateCount)
AS (SELECT [FirstName],
           [LastName],
           [Country],
           ROW_NUMBER() OVER(PARTITION BY [FirstName],
                                          [LastName],
                                          [Country]
           ORDER BY ID) AS DuplicateCount
    FROM [SampleDB].[dbo].[Employee])
DELETE FROM CTE
WHERE DuplicateCount > 1;

It removes the rows having the value of [DuplicateCount] greater than 1

https://www.sqlshack.com/different-ways-to-sql-delete-duplicate-rows-from-a-sql-table/