VBA Needed for my data cleaning problem

There are many ways to do a task in Excel VBA and I'm sure others will give you more efficient ways to do this but this should work.  You can add additional code if you want to remove the assumptions.

Sub FillNames()
    Dim i As Long
    Dim sName As String
    Dim nLastRow As Long
    
    ActiveSheet.UsedRange                   'reset the used range
    nLastRow = ActiveSheet.Cells.SpecialCells(xlCellTypeLastCell).Row  'assumes no other data below last person's data
    sName = ""
    
    For i = 1 To nLastRow               'assumes there will always be a name in row 1, column A
        If Cells(i, 1).Value = "" Then  'assumes Employee column is A which is column 1
            Cells(i, 1).Value = sName   'sets the current name in the empty cell
        Else
            sName = Cells(i, 1).Value   'assigns the current row's name
        End If
    Next i
End Sub