Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
   
   If Not Intersect(Target, Columns(3)) Is Nothing Then Columns(3).Replace What:=".", Replacement:=",", LookAt:=xlPart

End Sub

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

   Dim Numbs() As String
   Dim Numb As Variant
   Dim cell As Range
   
   If Target.Count = 1 Then
      With Worksheets(2)
         If InStr(1, Target.Value, "Название", vbTextCompare) > 0 Then
            .UsedRange.Interior.Color = Cells(1, 6).Interior.Color
            Numbs = Split(Target.Offset(, 1), ",", -1, vbTextCompare)
            For Each Numb In Numbs
               Set cell = .UsedRange.Find(What:=Numb, LookIn:=xlValues, LookAt:=xlWhole)
               If Not cell Is Nothing Then cell.Interior.Color = Cells(8, 6).Interior.Color
            Next Numb
         End If
         If Not Intersect(Target, Cells(8, 6)) Is Nothing Then
            For Each cell In .UsedRange
               If cell.Interior.Color <> Cells(1, 6).Interior.Color Then cell.Interior.Color = Target.Interior.Color
            Next cell
         End If
      End With
   End If

End Sub